Wyniki wyszukiwania - BazTech

1

Effect of solution and artificial aging heat treatment on the hardness, friction and wear properties of laser cladding and roll-formed 18Ni300 materials

Tang Zhaoqing, Li Weimin, Yang Zeyu, Wang Jinying

Materials Science Poland

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2024

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Vol. 42, No. 2

26--40

EN

18Ni300 is widely used in precision moulds, national defence, and other engineering fields due to its high strength and toughness, and because its properties can be greatly changed after heat treatment. In this research, the 18Ni300 cladding layer was fabricated on 18Ni300 substrate using the laser cladding method and a solid solution artificial aging treatment was carried out to analyse its macro morphology and metallographic organization. Comparison of hardness, friction, and wear of cladding layers manufactured by laser cladding and of materials produced by rolling was performed before and after heat treatment. The results show that the solution and artificial aging heat treatment has a significant effect on the microstructure of the cladding layer fabricated by laser cladding. There are obvious differences in the organization and morphology of different parts of the cladding layer before heat treatment; the metallographic organization and morphology of different parts of the cladding layer after heat treatment are the same. The trend of change of material hardness before and after heat treatment is the same in that the cladding layer is greater than the rolled material and the hardness of the material after heat treatment is much greater than the hardness of the material before heat treatment. The hardness and wear resistance of the material after solution and artificial aging heat treatment has been significantly improved, and the impact on the rolled production material of the melted cladding layer manufactured by laser cladding is even greater.

2

Coaxial Laser Wire Deposition of AISI 316L steel - research on influence of processing parameters

Koruba Piotr, Radkiewicz Przemysław, Kędzia Jakub, Dziedzic Robert, Smuga Piotr, Reiner Jacek

Welding Technology Review

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2023

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R. 95

67--77

EN

Laser cladding technology is a well-established process, commonly used for deposition of improved-property coatings, repair of machine parts and additive manufacturing. Currently, in terms of application of laser cladding, the method based on powder deposition is much more common, as the use of an adapted nozzle allows the coaxial and direction-independent feeding of additional material into the weld pool. However, laser cladding with powder also has some significant drawbacks, e.g., limited powder feeding and melting efficiency, lower productivity and the resulting dust that poses a health risk to operators. The solution to these limitations is the use of additional material in the form of wire. To maintain the ability to coaxially feed the wire to the laser beam interaction point, a specialized cladding head is necessary. In mentioned system the laser beam, while being passed through the optical system, is divided into three separate beams that are focused on the substrate on the working point of the head. In this study, the COAX wire cladding head was integrated into the robot station and laser cladding process was carried out to determine the influence of the processing parameters on the deposition results. The parameters of the cladding system were identified, including the measurement of laser beam caustic. The experimental trials were carried out using AISI 316L wire deposited on S420MC substrate. The effect of the processing parameters on the geometry of the clad was determined with particular emphasis on the wire feeding.

3

Influence of laser and TIG cladding methods on microstructure morphology and hardness of Stellite 694 overlay deposited onto DS200+Hf alloy substrate

Gancarczyk Natalia, Gradzik Andrzej, Kościelniak Barbara, Gancarczyk Kamil, Góral Marek

Mechanik

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2023

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R. 96, nr 7

26--34

EN

In this paper the influence of cladding method - laser and TIG - on microstructure and properties of Stellite 694 coatings deposited onto DS200+Hf nickel based alloy substrate is presented. Manual TIG cladding process were carried out using LORCH V24 DC, laser cladding process was carried out using Yb:YAG, TruDisk 1000 TRUMPF. Cobalt alloy - Stellite 694 was used as a filler material. Effect of different cladding methods was examined based on chemical composition and microstructure analysis as well as hardness measurements of the deposited layers.

PL

W niniejszej pracy prowadzono ocenę morfologii składników fazowych mikrostruktury i właściwości warstwy ochronnej Stellite 694 na podłożu z żarowytrzymałego nadstopu niklu DS200+Hf, wytworzonej w procesach napawania elektrycznego (TIG) i laserowego. Napawanie elektryczne metodą TIG przeprowadzono z użyciem spawarki LORCH V24 DC, natomiast laserowe - za pomocą lasera dyskowego Yb:YAG, TruDisk 1000 firmy TRUMPF. Materiałem dodatkowym był stop kobaltu Stellite 694. Określono stopień oddziaływania źródła ciepła i warunków procesu na skład chemiczny napoiny, jej mikrostrukturę oraz twardość w mikroobszarach.

4

Study on overlap rate and machinability of selected laser melting of maraging steel

Yang Zeyu, Li Weimin, Liu Shufen, Gao Qi

Materials Science Poland

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2023

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Vol. 41, No. 2

368--382

EN

In order to investigate the material properties of maraging steel laser additive manufacturing, the cladding layers with different overlap rates on the surface of 18Ni300 were prepared by laser cladding technology, and the morphology, microstructure, and hardness of the cladding layer with different overlap rates were analyzed by various means. The results show that the macroscopic morphology of the cladding layer mainly presents three states under different overlap rates, and the change of overlap rate has no effect on the microstructure in the same area of the cladding layer, but does have an effect on the size of the cladding layer. In the end, the optimum overlap rate is 50%, the surface is smooth, the inner is free from defects, the bonding effect is good, and the metallographic structure is even with high hardness. Milling experiments were carried out on the material after laser additive manufacturing, and the surface morphology was observed, confirming a smooth and well-flattened surface with a roughness of 0.342 μm had been obtained. The suitable overlap rate can make the coating surface smoother, reduce the subsequent processing loss, and improve the production efficiency and powder utilization rate while ensuring the coating quality.

5

Effects of B content on wear and corrosion resistance of laser-cladded Co-based alloy coatings

Xia Rong, Zhang Kun, Shu Fengyuan, Zhang Xin, Yan Liying, Li Cheng

Materials Science Poland

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2023

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Vol. 41, No. 4

13--23

EN

To improve the surface properties of Ti alloy, (Co34Fe8Cr29Ni8Si7)100–x Bx alloy, coatings were prepared by laser cladding. The coatings—mainly composed of TiCr, Fe0.1Ti0.18V0.72, CoTi, Ti2Ni, and TiB—and amorphous phases were investigated in terms of microstructure, wear resistance, and corrosion resistance. The results showed that the microhardness of the Co-based coatings first increased and then decreased with the increase of B content. When the B content was 6%, the microhardness of the coating increased up to 1210 HV0.2 which was 3.4 times that of TC4 alloy substrate. The coatings exhibited diverse wear mechanisms that gradually transitioned from severe fatigue spalling and oxidative wear to slightly abrasive wear. The corrosion current density of Co-based coatings in 3.5 wt% NaCl solution first increased and then decreased as B contents increased. Coatings with 4% B content, however, exhibited the best corrosion resistance, which was most suitable for improving the corrosion resistance of Ti alloy.

6

Effects of Y2O3 on Microstructure and Corrosion Properties of Laser Cladding Composite Coatings on 304 Stainless Steel Substrate

Yu Jinling, Zhentai Zheng, Li Shuai, Guo Donghui, Chang Liang

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 2

447--453

EN

Ni625/WC composite coatings added with different amounts of Y2O3 were prepared on the surface of 304 stainless steels by laser cladding. This study focused on the microstructure characteristics, microhardness, and corrosion performances of Ni625/WC composite coatings. The results showed that Y2O3 can effectively improve the corrosion resistance of the composite coatings. The microstructure from the bottom to the surface of composite coatings consists of plane crystal, cellular crystal, columnar crystal and equiaxed crystal. The Y2O3 content of optimum composite coating was 1.0%. Its microhardness was three times that of matrix material. In addition, the corrosion current density of the composite coating was only 2% of Ni625/WC coating, which was attributed to the good properties of Y2O3 and appropriate Y2O3 refined microstructure.

7

Study on Improvement of Surface Properties of SKD61 Powder on S45C Using Laser Cladding

Kim Cheol-Woo, Yoo Hyo-Sang

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 4

1465--1468

EN

In this study, we investigated the effect of cladding on structural carbon steel (S45C) using 5%Cr-1.5%Mo-Fe powder (SKD61), which is expected to show economically efficient production of die-casting parts. The process conditions were performed under argon atmosphere using a diode laser source with specialized wavelength of 900-1070 nm, and the output conditions were 3, 4, and 5 kW, respectively. After the cladding was completed, the surface coating layer’s shape and the microstructure were analyzed. The hardness test was carried out with Micro Vickers hardness tester under 500 gram-force along the normal line at the interval of 0.2 mm from the surface to core direction on the cross-sectional area. In addition, polarization curve test of the surface coating layer was performed to investigate the corrosion resistance characteristics.

8

Microstructure, tribological performances, and wear mechanisms of laser-cladded TiC-reinforced NiMo coatings under grease-lubrication condition

Weixin Zhu, Dejun Kong

Materials Science Poland

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2021

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Vol. 39, No. 3

395--409

EN

NiMo-5%TiC, NiMo-15%TiC, and NiMo-25%TiC coatings were prepared on GCr15 steel by laser cladding (LC). The microstructure and the phases of the obtained coatings were analyzed using ultra-depth-of-field microscopy (UDFM) and X-ray diffraction (XRD), respectively. A ball-on-disk wear test was used to analyze the friction-wear performance of the substrate and the NiMo-TiC coatings under grease-lubrication condition. The results show that the grain shape of NiMo-TiC coatings is dendritic. The wear resistance of NiMo-TiC coatings is improved by the addition of TiC, and the depths of the worn tracks on the substrate and on the NiMo-5%TiC, NiMo-15%TiC, and NiMo-25%TiC coatings are 4.183 μm, 2.164 μm, 1.882 μm, and 1.246 μm, respectively, and the corresponding wear rates are 72.25 μm3/s/N, 32.00 μm3/s/N, 18.10 μm3/s/N, and 7.99 μm3/s/N, respectively; this shows that the NiMo-25%TiC coating has the highest wear resistance among the three kinds of coatings. The wear mechanism of NiMo-TiC coatings is abrasive wear, and the addition of TiC plays a role in resisting wear during the friction process.

9

Study on Improvement of Surface Properties of Low Carbon Steel Using Laser Cladding

Kim Cheol-Woo, Yoo Hyo-Sang, Jeon Jae-Yeol, Cho Kyun-Taek, Choi Se-Weon

Archives of Metallurgy and Materials

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2021

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Vol. 66, iss. 4

1033--1036

EN

Laser cladding is a method that can be applied to repair the crack and break on the mold and die surfaces, as well as generate new attributes on the surface to improve toughness, hardness, and corrosion resistance. It is used to extend the life of the mold. It also has the advantages of superior bonding strength and precision coating on a local area compared with the conventional thermal spraying technology. In this study, we investigated the effect of cladding on low carbon alloy steel using 18%Cr-2.5%Ni-Fe powder (Rockit404), which showed high hardness on the die surface. The process conditions were performed in an argon atmosphere using a diode laser source specialized for 900-1070 nm, and the output conditions were 5, 6, and 10 kW, respectively. After the cladding was completed, the surface coating layer’s shape, the hardness according to the cross-section’s thickness, and the microstructure were analyzed.

10

Laser Cladding of WC/T-800 Cermet: Fabrication, Microstructure and Wear Properties

Kim Kyoung-Wook, Kim Young-Kyun, Park Sun-Hong, Lee Kee-Ahn

Archives of Metallurgy and Materials

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2021

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Vol. 66, iss. 3

713--717

EN

This study fabricated a WC/T-800 cermet coating layer with Co-Mo-Cr (T-800) powder and WC powder using laser cladding, and analyzed its microstructure, hardness and wear properties. For comparison, casted bulk T-800 was used. Laser cladded WC/T-800 cermet coating layer showed circular WC phases in the Co matrix, and dendritic laves phases. The average laves phase size in the cermet coating layer and bulk T-800 measured as 7.9 µm and 60.6 µm, respectively, indicating that the cermet coating layer had a relatively finer laves phase. Upon conducting a wear test, the cermet coating layer added with WC showed better wear resistance. In the case of laser cladded WC/T-800 cermet coating layer, abrasion wear was observed; on the contrary, the bulk T-800 showed pulled out laves phases. Based on the above findings, the WC/T-800 cermet coating layer using laser cladding and the relationship between its microstructure and wear behavior were discussed.

11

New approach towards the machining process after laser cladding

Shen Xuehui, Su Hao, Wang Jiatian, Zhang Changsheng, Xu Chonghai, Bai Xiaolan

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 1

136--152

EN

As a chip-free and high-efficiency three-dimensional forming technology, laser cladding has been successfully applied in the green manufacturing and remanufacturing of some high-end engineering parts/components. However, in most cases, cladding coatings need to be machined due to the poor surface finishing by sole laser cladding technique. The study aims to explore an effective way to replace the current machining process after laser cladding, which is supposed to be incapable of satisfying the various technical requirements of some high-demand engineering parts/components. With this purpose, three new surface strengthening processes, i.e. ultrasonic roller burnishing at ambient temperature (URB), ultrasonic roller burnishing at warm temperature (UWB), and UWB coupled with continuous heat treatment (UWB/HT), were proposed and comparatively explored. The contact stresses between the contact pairs in URB were calculated and analyzed in theory. A set of ultrasonic roller burnishing equipment was self-manufactured to perform the experiment. Comparing with the conventional process, the three new processes were evaluated mainly from aspects of surface finishing, the adhesion behavior and corrosion resistance of the finished surface. Summarily, ultrasonic warm burnishing coupled with continuous heat treatment (UWB/HT) is considered to have the greatest potential to achieve the effective machining after laser cladding with excellent surface finishing over the other two strategies, which is expected to further advance the application of laser cladding technique particularly in the fabrication of some high-demand products serving in harsh conditions.

12

Remanufacturing and surface modification in micro-areas by laser beam and microTIG methods

Połaski Przemysław, Jakubowski Jerzy

Welding Technology Review

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2020

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R. 92, nr 1

31--43

EN

Over the past years, intensive development of welding technologies that enable precise impact on the workpiece has been observed. The laser technology is the most known and commonly used tool for precise machining, both in terms of obtaining the appropriate geometry and heat distribution. This technology is now easily available, but it still has many limitations in its "basic edition". An attractive alternative in machining micro-areas can be the arc method ‒ microTIG, which is a modification of the TIG method. The work compares the effects of cladding of selected pairs of substrate materials using the microTIG method and a laser beam. The results of microscopic tests and hardness measurements of deposits made with a laser beam and the microTIG method are presented. The advantage of cladding with the microTIG method was the possibility of obtaining deposits with a lower dilution of the substrate material in the clad weld compared to laser cladding. On the other hand, clad welds produced with the laser beam had a significantly smaller amount of welding defects.

PL

Na przestrzeni ostatnich lat można było zaobserwować intensywny rozwój technologii spawalniczych umożliwiających precyzyjne oddziaływanie na materiał obrabiany. Najbardziej znanym i powszechnie stosowanym narzędziem do precyzyjnej obróbki, zarówno pod względm uzyskania odpowiedniej geometrii jak i dozowania ciepła były i są lasery. Technologia ta jest obecnie łatwo dostępna, jednak dalej w swoim "podstawowym wydaniu" ma wiele ograniczeń. Atrakcyjną alternatywą w obróbce mikroobszarów może być metoda łukowa - mikroTIG będąca modyfikacją metody TIG. W pracy dokonano porównania efektów napawania wybranych par materiałów podłoża metodą mikroTIG i wiązką lasera. Przedstawiono wyniki badań mikroskopowych oraz twardości napoin wykonanych wiązką lasera i metodą mikroTIG. Zaletą napawania metodą mikroTIG była możliwość uzyskania napoin o mniejszym udziale materiału podłoża w napoinie, w porównaniu do napawania laserem. Z kolei w napoinach wykonanych metodą laserową występowała znacznie mniejsza ilość niezgodności spawalniczych.

13

Sustainable manufacturing: re-contouring of laser cladding restored parts by machining method with cutting energy management

Zhang Peirong, Du Jin, Zhou Tingting, Su Guosheng, Huang Weimin, Liu Zhanqiang

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 2

167--176

EN

Laser cladding has been commonly utilized for restoring high value-added parts. However, the poor surface quality becomes key technological barrier which restricts its widespread applications. In the paper, re-contouring strategies by machining method are explored for minimal energy consumption as well as required surface roughness. Firstly, the effect of structural characteristics of the laser-cladded workpiece on specific cutting energy was explored by means of layer-by-layer turning and orthogonal cutting. Results indicated that the specific cutting energy increased, and the machining chatter/vibration exacerbated with decreasing coating thickness under fixed cutting parameters. The reason can be summarized as a result of the effect of elastoplastic deformation behavior across the interface. Then, the influences of depth of cut and feed on specific cutting energy in finish turning were addressed. Results indicated that the specific cutting energy reduced with increasing depth of cut and feed in the form of power functions. In addition, energy efficiency decreased with an increase in uncut chip thickness and cutting speed. On basis of this work, large feed and low cutting speed with the adoption of wiper inserts were recommended for minimizing energy consumption within surface roughness requirement.

14

Effect of turning-induced initial roughness level on surface roughness and residual stress improvements in subsequent burnishing

Zhang Peirong, Du Jin, Zhang Hui, Su Guosheng, Shen Xuehui, Huang Weimin, Liu Zhanqiang

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 3

241--253

EN

The hydraulic support column of comprehensive mining equipment is the most important part, subjecting to corrosion, wear and collision. The scrapped columns are restored by laser cladding to replace plating process for enhancing service life. All that is required after laser cladding is subtractive machining to improve the surface quality of the laser cladded coatings. This work focused on the remanufacturing machining strategy for re-contouring the laser cladding restored columns. First, surface roughness model of the laser cladded coatings by turn-burnishing was presented based on the surface generation mechanism. Then the effect of turning-induced roughness level on the surface roughness improvements by subsequent burnishing is addressed. Results indicated that the reduction of surface roughness by burnishing showed positive correlation with the feed in initial turning with conventional inserts, while was negatively correlated with the feed in initial turning with wiper inserts. In addition, the initial turning-induced surface roughness level generated great influence on the residual stress improvement in subsequent burnishing. Based on the findings, proper remanufacturing machining strategies for re-contouring the laser cladding-restored hydraulic support columns were presented.

15

The Impact of Material Selection on Durability of Exhaust Valve Faces of a Ship Engine – A Case Study

Smoleńska Hanna, Kończewicz Włodzimierz, Bazychowska Sylwia

Advances in Science and Technology. Research Journal

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2020

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Vol. 14, no 3

165--174

EN

Two alloys were used in order to extend the service life of marine engine exhaust valve head. Layers of cobalt base alloys were made of the powders with chemical composition as follow: the layer marked L12; C-1.55%; Si-1.21%; Cr-29.7%; W-9%; Ni-2%; Mo<0.01%; Fe-1.7%; Co-54.83% and the layer marked N; C-1.45%; Co-38.9%; Cr24.13%; Ni-10.43%; W-8.75%; Fe-7.64%; Mo-7.56%; Si-2.59%. Base metal was valve steel after heat treatment. It was consisted of: C-0,374%; Cr-9,34%; Mn-0.402%; Ni-0.344%; Si-2.46%; Mo-0.822%; P-0.0162%; S-0.001%. Layers on the valve faces were produced by laser cladding using the HPDL ROFIN DL020 laser. Grinding treatment is a very popular form of regeneration of seat and valve plug adhesions. Properly performed grinding operation ensures dimensional and shape accuracy of the surface from 7 to 5 accuracy class and surface roughness Ra not less than 0.16 μm, depending on the object and method of grinding. The 75H and 150S types are a significantly simplified form of valve plug face grinders. Finishing treatment was carried out with a Chris-Marine AB75H sander on a sanding stand equipped with a compressed air system - the stand was designed by the author. The sander has been set up to the surface of the valve stem so that the grinding angle of the valve faces is 30°+10°. A flat grinding wheel T1CRA54–K was used for machining. The plunge feed was 0.01 mm/rev. The thickness of the welded layer after grinding was 1.2 mm. Both valves were installed in the ship’s engine and were used in real life. After 2000 hours of operation, the valve marked N was damaged. The valve marked L12 showed no damage and was in operation for the next 1000 hours.

16

Sliding wear examination of new protecting coatings on railway buffer heads

Gamon Wojciech

Journal of KONBiN

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2019

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Vol. 49, iss. 4

401--419

EN

The paper presents the results of tests of sliding wear of bronze coatings made on the surface of specimen made of S355J2 steel by laser cladding method. On the basis of the conducted tests it was found that the wear of the specimens with CuAl9Fe3 bronze coating is characterized by average values which are close to lubricated specimens. In addition, the registration of friction coefficients of particular couples showed very similar characteristics of these two friction couples and friction coefficient values at a very similar level. This allows to assume that the currently used method of protecting railway buffer heads, consisting of periodically covering their surface with lubricant, can be replaced with another, more durable, based on bronze protection coatings.

PL

W artykule przedstawiono wyniki badań zużycia ściernego powłok z brązów wytworzonych na powierzchni próbek wykonanych ze stali S355J2 metodą napawania laserowego. Na podstawie badań stwierdzono, że zużycie próbek z napoinami z brązu CuAl9Fe3 cechuje się wartościami średnimi zbliżonymi do próbek smarowanych. Ponadto, rejestracja współczynników tarcia poszczególnych skojarzeń wykazała bardzo zbliżone charakterystyki tych dwóch par ciernych oraz wartości współczynników tarcia na bardzo podobnym poziomie. Pozwala to na założenie, że obecnie stosowana metoda zabezpieczania zderzaków kolejowych, polegająca na okresowym pokrywaniu ich powierzchni smarem, może zostać zastąpiona inną, trwalszą, bazującą na wykonywaniu powłok zabezpieczających z brązów.

17

Laser cladding of Co-based metallic powder at cryogenic conditions

Lisiecki A., Ślizak D., Kukofka A.

Journal of Achievements in Materials and Manufacturing Engineering

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2019

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Vol. 95, nr 1

20--31

EN

Purpose: of this paper was demonstration a novel technique of laser cladding by experimentally composed Co-based metallic powder and forced cooling of the substrate by liquid nitrogen under cryogenic conditions, at the temperature -190°C, for producing clad layers with enhanced microstructure characteristic and properties. Design/methodology/approach: Technological tests of laser cladding were conducted by means of a high power fibre laser HPFL with maximum output power 3.0 kW, and six-axis robot. The experimental Co-based powder was composed for providing high abrasive wear resistance, high resistance for impact load, and also for corrosion resistance at elevated temperature. The unique and novel technique of forced cooling of the substrate was provided by immersing the specimens in the liquid nitrogen bath. The three coaxial nozzle head was designed and custom made to provide precise deposition of the powder delivered into the laser beam irradiation region. The scope of the study included tests of conventional laser cladding at free cooling in ambient air in a wide range of processing parameters, and also trials of laser cladding under cryogenic conditions. The test clad layers produced by conventional laser cladding and by the novel technique of laser powder deposition under cryogenic conditions were investigated and compared. Findings: The obtained results indicate that the novel technique of forced cooling the substrate by liquid nitrogen bath provides lower penetration depth, as well as low dilution of the clad, and also provides higher hardness of the clads. Additionally, it is possible shaping the geometry of the individual bead, providing high reinforcement and low width. Research limitations/implications: The presented results are based just on preliminary test of the novel technique of laser cladding under cryogenic conditions. Therefore, further study and detailed analyse of the influence of the cooling rate on the quality, microstructure, and properties of the deposited coatings are required. Practical implications: The study is focused on practical application of the novel technique for manufacturing of wear resistance coatings characterised with enhanced performance compared to conventional range of application of the laser cladding. Originality/value: Novel technique of laser cladding at forced cooling under cryogenic conditions was demonstrated. The powder used for cladding trials was experimentally composed (not commercially available). The experimental stand custom made was used with custom made powder feeding rate, and also with custom made coaxial nozzle head.

18

Modelling aspects of laser cladding of bioactive glass coatings on ultrafine-grained titanium substrates

Bajda Szymon, Krzyzanowski Michal

Computer Methods in Materials Science

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2019

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Vol. 19, No. 3

138--149

EN

Titanium alloys, due to their exceptional mechanical properties and biocompatibility, are commonly used to produce medical implants nowadays. However, the presence of such elements as aluminium and vanadium can be harmful to human health. One of the possible solutions could be replacing the titanium alloys with ultrafine-grained commercially pure titanium (cpTi). The yield and also the ultimate strength of cpTi can exceed 1000 MPa. One of the most promising methods in manufacturing medical implants with improved biological fixation is laser cladding in which bioactive glass coatings are imposed on metallic substrates. The aim of this work is development of a 3D numerical model of the above mentioned additive manufacturing process. The obtained model is able to predict the stress-strain and temperature distributions during the processing. A sequentially coupled finite element (FE) model of laser cladding has been developed by applying element birth and death technique to calculate the transient temperature fields used in the stress analysis. The concentrated volumetric heat source from the laser beam moving along the metal surface has been represented by the Gaussian distribution in the radial and exponential decay in the depth direction. The developed FE based numerical model is capable to support the optimal design of such advanced multi-layered structural materials using the laser cladding technique.

PL

Stopy tytanu są obecnie powszechnie stosowane do produkcji implantów medycznych ze względu na wyjątkowe własności mechaniczne i biokompatybilność. Jednakże obecność takich pierwiastków jak aluminium i wanad może być szkodliwa dla zdrowia ludzkiego. Jednym z możliwych rozwiązań tego problemu może być zastąpienie stopów tytanu ultradrobnoziarnistym komercyjnie czystym tytanem (cpTi), którego granica plastyczności i wytrzymałość na rozciąganie cpTi może przekraczać nawet 1000 MPa. Jedną z najbardziej obiecujących metod produkcji implantów medycznych jest napawanie laserowe, w którym powłoki szkła bioaktywnego są nakładane na podłoża metaliczne. Celem pracy było opracowanie modelu numerycznego 3D w/w procesu wytwarzania przyrostowego. Otrzymany model jest w stanie przewidywać rozkłady naprężeń, odkształceń i temperatur występujących w trakcie procesu. Opracowano model sekwencyjny napawania laserowego wykorzystując metodę elementów skończonych (MES) i technikę dezaktywacji i aktywacji elementów skończonych, co pozwoliło obliczyć przejściowe pola temperatury, które wykorzystano następnie do analizy naprężeń. Skoncentrowane objętościowe źródło ciepła wiązki laserowej przemieszczającej się wzdłuż powierzchni metalu było opisane za pomocą rozkładu Gaussa. Opracowany model numeryczny może wspomóc projektowanie i wytwarzanie zaawansowanych wielowarstwowych materiałów z wykorzystaniem techniki napawania laserowego.

19

Fabrication and Macroscopic Properties of Filler Metal (BCuP-5) on Cu-plate using Laser Cladding Process

Lee Kee-Ahn, Park Joo Hyun, Joo Yeun Ah

Archives of Metallurgy and Materials

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2019

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Vol. 64, iss. 2

559--563

EN

This study stacked a thin, dense BCuP-5 (Cu-Ag-P based filler metal) on a Cu-plate using the laser cladding (L.C) process to develop a method to manufacture Ag reducing multilayer clad electrical contact material with an Ag-M(O)/Ag/Cu/BCuP-5 structure. Then, the microstructure and macroscopic properties of the manufactured BCuP-5 coating layer were analyzed. The thickness of the manufactured coating layer was approximately 1.7 mm (maximum). Microstructural observation of the coating layer identified Cu, Ag and Cu-Ag-Cu3P ternary eutectic phases like those in the initial BcuP-5 powder. To evaluate the properties of the manufactured coating layer, hardness and adhesion strength tests were performed. The average hardness of the laser cladded coating layer was 183.2 Hv, which is 2.6 times greater than conventional brazed BcuP-5. The average pull-off strength measured using the stud pull test was 341.6 kg/cm2. Cross-sectional observation of the pulled-off material confirmed that the coating layer and substrate maintained a firm adhesion after pull-off. Thus, the actual adhesion strength of Cu/BcuP-5 was inferred to be greater than 341.6 kg/cm2. Based on the above findings, it was confirmed that it is possible to manufacture a sound Ag reducing multilayer clad electrical contact material using the laser cladding process.

20

Napawanie laserowe warstw kompozytowych na osnowie stopu Inconel 625

Janicki D., Górka J., Kotarska A.

Welding Technology Review

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2018

|

R. 90, nr 9

6--12

PL

Artykuł prezentuje wyniki badań procesu napawania laserem diodowym warstw wierzchnich kompozytowych na osnowie stopu niklu Inconel 625 wzmacnianych cząstkami WC oraz Cr3C2. Określono wpływ energii linowej napawania oraz morfologii cząstek fazy umacniającej (FU) na stopień jej rozpuszczenia w osnowie warstwy. Ponadto, określono wpływ morfologii cząstek FU na odporność erozyjną warstw.

EN

Inconel 625-based composite coatings reinforced by WC and Cr3C2 particles have been produced via a diode laser cladding process. The effect of heat input level and morphology of the reinforcing particles on the degree of their dissolution has been established. Additionally, the influence of the morphology of the reinforcing particles on the erosive wear behaviour of the coatings was studied.