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1

The effect of the remelting and laser surface alloying of titanium grade 5 (Ti6-Al-4V) on erosive wear resistance

Poloczek Tomasz, Kwaśny Waldemar, Czupryński Artur

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2022

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Vol. 66, No. 2

23--32

EN

The article presents the effect of the remelting and alloying of titanium grade 5 (Ti6-Al-4V) on erosive wear resistance (in accordance with the ASTM G76-04 standard). The study involved tests concerning the effect of graphite on the in-situ synthesis of titanium carbide during alloying performed using a Trudisk 3302 disk laser. The study also involved hardness measurements of individual beads as well as macro and microscopic tests. The tests involving the use of a Phenom World PRO scanning electron microscope provided with an EDS analyser as well as the X-ray phase analysis revealed the possible synthesis of titanium carbide during the laser alloying of the titanium surface with graphite. The erosive wear resistance of beads reinforced with composite particles was higher than that of the material in the as-received state, yet lower than that of the material remelted without the use of the alloying material.

PL

W artykule przedstawiono wpływ przetapiania oraz stopowania tytanu Grade 5 (Ti6-Al-4V) na odporność erozyjną, zgodnie z normą ASTM G76-04. Przebadano wpływ grafitu na możliwość syntezy in situ węglika tytanu w procesie stopowania laserowego, wykorzystując laser dyskowy Trudisk 3302. Wykonano pomiary twardości poszczególnych ściegów oraz badania metalograficzne makro- i mikroskopowe. Przeprowadzone badania na skaningowym mikroskopie elektronowym PhenomWorld PRO, wyposażonym w analizator EDS, oraz rentgenowska analiza fazowa wykazały możliwość syntezy węglika tytanu w procesach stopowania laserowego powierzchni tytanu grafitem. Odporność na zużycie erozyjne ściegów wzmocnionych cząstkami kompozytowymi wykazała polepszenie własności względem materiału w stanie dostawy, natomiast osiąga niższe wartości względem materiału przetopionego bez udziału materiału stopującego.

2

Crystallization of the Structural Components of Multiple Remelted AlSi9Cu3 Alloy

Matejka M., Bolibruchova D., Kuriš M.

Archives of Foundry Engineering

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2021

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Vol. 21, iss. 2

41--45

EN

At present, Al-Si-Cu based alloys (with a typical representative AlSi9Cu3 alloy) represent more than half of the castings used in various industries (automotive, aerospace and electrical engineering). These are most often sub-eutectic (exceptionally eutectic) alloys with a content of 6 to 13 wt. % Si and 1 to 5 wt. % Cu. The aim of the paper is to point out the importance of the evaluation of input raw materials that determines the overall properties of the casting and the costs invested in its production. A negative impact on performance can be expected when using an alloy made up of a high proportion of recycled material, despite its economic benefits. Experimental alloys were evaluated based on the results of crystallization process and a combination of scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and deep etching. The effect of remelting and increasing the remelted returnable material in the batch was manifested especially in the crystallization of iron-rich phases. The negative effect of remelting on the structural components was manifested after the fourth remelting. Gradual increase of remelted returnable material in the batch causes harmful changes in the crystallization process.

3

Study of AlSi9Cu3 Alloy Crystallization Process with Increased Iron Content at Different Number of Remelts

Matejka M., Bolibruchova D., Kasińska J., Kuriš M.

Archives of Foundry Engineering

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2020

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Vol. 20, iss. 1

79--83

EN

Monitoring the solidification process is of great importance for understanding the quality of the melt, for controlling it, and for predicting the true properties of the alloy. Solidification is accompanied by the development of heat, the magnitude of which depends on the different phases occurring during solidification. Thermal analysis is now an important part of and tool for quality control, especially when using secondary aluminium alloys in the automotive industry. The effect of remelting on the change of crystallization of individual structural components of experimental AlSi9Cu3 alloy was determined by evaluation of cooling curves and their first derivatives. Structural analysis was evaluated using a scanning electron microscope. The effect of remelting was manifested especially in nucleation of phases rich in iron and copper. An increasing number of remelts had a negative effect after the fourth remelting, when harmful iron phases appeared in the structure in much larger dimensions.

4

Measurements and numerical simulations of laser hardening and remelting thermal cycles

Kik T., Wyględacz B.

Journal of Achievements in Materials and Manufacturing Engineering

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2019

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Vol. 96, nr 2

69--82

EN

Purpose: of these researches was to investigate the influence of thermal cycles recording conditions and comparing them with the calculated by FEM. This approach allows proposing a new way of determining the technological conditions of the process, based on numerical analyses. Design/methodology/approach: Thermal cycles of high power diode laser hardening and remelting was recorded and calculated by FEM. Results of metallographic examinations were compared with numerical simulations results, as well as the thermographic pictures. Acquisition errors during the thermal cycles were also defined. Findings: Due to the fact that the it was used FEM, comparison of the numerical analyses with real test results was performed for laser hardening and remelting process. Research limitations/implications: For complete information it is needed to collect bigger database of the results and prepare also hardness calculation model for WCL steel. Practical implications: The result of the presented work is to signal a methodology that allows obtaining information on the impact of the parameters of the laser hardening and remelting process on the properties of the treated samples. Not without significance is the fact that the use of FEM eliminates in this case a lot of errors that in real tests can distort the result. Originality/value: The researches were provided for high power diode laser hardening and remelting. The influence of heat input on layers properties and theirs structure was defined. Results were compared with thermographic pictures and calculated cases.

5

Dual Speed Laser Remelting for High Densification in H13 Tool Steel Metal 3D Printing

Jung Im Doo, Choe Jungho, Yun Jaecheol, Yang Sangsun, Yang Dong-Yeol, Kim Yong-Jin, Yu Ji-Hun

Archives of Metallurgy and Materials

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2019

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Vol. 64, iss. 2

571--578

EN

The densification behavior of H13 tool steel powder by dual speed laser scanning strategy have been characterized for selective laser melting process, one of powder bed fusion based metal 3d printing. Under limited given laser power, the laser re-melting increases the relative density and hardness of H13 tool steel with closing pores. The single melt-pool analysis shows that the pores are located on top area of melt pool when the scanning speed is over 400 mm/s while the low scanning speed of 200 mm/s generates pores beneath the melt pool in the form of keyhole mode with the high energy input from the laser. With the second laser scanning, the pores on top area of melt pools are efficiently closed with proper dual combination of scan speed. However pores located beneath the melt pools could not be removed by second laser scanning. When each layer of 3d printing are re-melted, the relative density and hardness are improved for most dual combination of scanning. Among the scan speed combination, the 600 mm/s by 400 mm/s leads to the highest relative density, 99.94% with hardness of 53.5 HRC. This densification characterization with H13 tool steel laser re-melting can be efficiently applied for tool steel component manufacturing via metal 3d printing.

6

Application of Natural and Artificial Ageing on Multiply Remelted AlSi9Cu3 Alloy

Matejka M., Bolibruchova D.

Archives of Foundry Engineering

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2019

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iss. 2

60--66

EN

This article focuses on the study of the influence of remelting and subsequent natural and artificial ageing on the structure of recycled AlSi9Cu3 alloy with increased iron content. The assessed changes in eutectic silicon and iron-based intermetallic phases were carried out using optical and scanning electron microscopy. The degradation of the eutectic silicon morphology due to remelting occurred only at the highest numbers of remelting. The effect of remelting the investigated alloy, which is accompanied by a gradual increase in wt. % Fe, began to manifest significantly through a change in the length of the ferric phases after the fourth remelting. As expected, the artificial ageing process has proven to be more effective than natural ageing. It has led to a change in the eutectic silicon morphology and has been beneficial in reducing the lengths of adverse ferric phases. The use of alloys with higher numbers of remelting, or with greater “contamination”, for the manufacture of shape-challenging castings is possible when using a suitable method of eliminating the negative factors of the remelting process. The results of our investigation show a suitable method of the above elimination the application of heat treatment T5 – via artificial ageing.

7

Advanced Applications of Microplasma Welding

Golański D., Chmielewski T., Skowrońska B., Rochalski D.

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2018

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Vol. 62, No. 5

53--63

EN

The article discusses microplasma arc applications in welding, surfacing and remelting processes, describes the effect of microplasma arc and its burning conditions as well as presents the properties and the application range of plasma welding. In addition, the article presents examples of microplasma welded joints of thin elements and discusses the application of microplasma arc in surfacing and remelting as well as indicates advantageous features of plasma arc and its application potential as an alternative to other welding power sources.

PL

Omówiono zagadnienia związane z łukiem mikroplazmowym wykorzystywanym w procesach spawania, napawania i przetapiania. Scharakteryzowano istotę działania oraz warunki jarzenia się łuku plazmowego. Podano właściwości oraz zakres zastosowania spawania plazmowego. Zaprezentowano przykłady złączy cienkich elementów spawanych mikroplazmowo. Omówiono na przykładach wykorzystanie łuku mikroplazmowego w procesach napawania oraz przetapiania. Wskazano na korzystne cechy łuku plazmowego oraz jego potencjał aplikacyjny jako alternatywę dla innych spawalniczych źródeł ciepła.

8

Influence of Remelting AlSi9Cu3 Alloy with Higher Iron Content on Mechanical Properties

Matejka M., Bolibruchova D.

Archives of Foundry Engineering

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2018

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Vol. 18, iss. 3

25--30

EN

The paper deals with influence of multiple remelting on AlSi9Cu3 alloy with higher iron content on chosen mechanical properties. Multiple remelting may in various ways influence mechanical, foundry properties, gas saturation, shrinkage cavity, fluidity etc. of alloy. Higher presence of iron in Al-Si cast alloys is common problem mainly in secondary (recycled) aluminium alloys. In Al-Si alloy the iron is the most common impurity and with presence of other elements in alloy creates the intermetallic compounds, which decreases mechanical properties. Iron in the used alloy was increased to about 1.4 wt. %, so that the influence of increased iron content can be investigated. In the paper, the effect of multiple remelting is evaluated with respect to the resulting mechanical properties in cast state, after the heat treatment (T5) and after natural aging. From the obtained results it can be concluded that the multiple remelting leads to change of chemical composition and affect the mechanical properties.

9

Application of the Finite Elements Method for computer simulation of properties of surface layers

Śliwa A.

Archives of Materials Science and Engineering

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2017

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Vol. 86, nr 2

56--85

EN

Purpose: The work presents the application of the Finite Elements Method in a computer simulation whose aim is to determine the properties of PVD and CVD coatings on various substrates and to optimise parameters of a laser surface treatment process of surface layers of tool steels. Design/methodology/approach: The article discusses the application of the finite elements method for simulating the determination of stresses and microhardness of Ti+TiN, Ti+Ti(CN) and Ti+TiC coatings obtained in a magnetron PVD process on a substrate of sinter high-speed steel, of Ti/Ti(C,N)/CrN, Ti/Ti(C, N)/(Ti, Al)N, Ti/(Ti, Si)N/(Ti, Si)N, Cr/ CrN/CrN, Cr/CrN/TiN and Ti/DLC/DLC coatings obtained in a PVD and CVD process on magnesium alloys, of graded and monolayer coatings (Ti, Al)N, Ti(C,N) produced with the PVD arc technique on a substrate of sintered carbides, cermets and oxide tool ceramics and tool steel remelted and alloyed with a high-performance diode laser (HPDL). Modeling of stresses was performed with the help of finite element method in ANSYS and MARC environment, and the experimental values of stresses were determined based on the sin2Ψ. Findings: The models presented satisfy the assumed criteria, and they can be applied for the determination of properties of surface layers and optimisation of PVD and CVD processes and laser alloying and remelting. The results of a computer simulation correlate with experimental results. The models developed allow to largely eliminate costly, timeconsuming and specialist experiments which have to be done during investigations for the benefit of computer simulations. Research limitations/implications: To be able to assess the possibility of application of surface layers, a computer simulation of other properties of coatings has to be additionally carried out, and a strength analysis has to be made of other coatings coated onto various substrate materials. Originality/value: value Computer simulation and modelling is an interdisciplinary field necessary for the development of science and technology, enabling to perform direct visualisation of properties, which cannot be identified in experimental observations. The purpose of computer simulation and modelling is to improve the ability to predict results and to optimise solutions.

10

Optymalizacja procesu selektywnego spiekania laserowego w celu zmniejszenia chropowatości powierzchni wykonanych części

Stwora A.

Mechanik

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2014

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R. 87, nr 12

999--1001

PL

Przedstawiono możliwości poprawienia jakości powierzchni elementów wykonywanych metodami przyrostowymi selektywnego spiekania/topienia laserowego (SLS/SLM) poprzez optymalizację parametrów spiekania (prędkości skanowania, czasu naświetlania, odległości pomiędzy punktami spiekania, mocy wiązki). Zaprezentowano również wpływ podwójnego naświetlenia pojedynczej warstwy, tzw. remelting, na chropowatość powierzchni wykonanego detalu.

EN

The paper presents methods of improvement of surface roughness of the components by means of the Selective Laser Sintering additive process through optimization of melting/ /sintering (SLS/SLM) parameters (scanning speed, exposure time, point to point distance, laser beam power). Reference is also made to influence of double exposure (remelting) on surface roughness of the components.

11

Wytop staliwa dwufazowego sposobem odzyskowym

Bartocha D.

Archives of Foundry Engineering

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2014

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Vol. 14, iss. 3 spec.

3--8

PL

W pracy przedstawiono wyniki próbnych wytopów staliwa GX2CrNiMoCuN25-6-3-3 przeprowadzonych w otwartym laboratoryjnym piecu indukcyjnym sposobem odzyskowym. Wytopy polegały na przetopieniu złomu staliwa duplex, a zabiegi ograniczono tylko do końcowego odtlenienia. W ramach każdego wytopu wykonane zostały odlewy próbne schodkowe. Przedstawiono wyniki badań składu chemicznego i określono jego zmiany w różnym stadium wytopu. Na podstawie badań mikrostruktury i symulacji krzepnięcia odlewów próbnych określono wpływ szybkości stygnięcia na strukturę badanego staliwa.

EN

In the article the results of trial melts of cast steel grade GX2CrNiMoCuN25-6-3-3 conducted in an open laboratory inductive furnace with regenerative method are presented. Melts consisted on remelting scrap of duplex cast steel, and metallurgical treatment is limited only to the final deoxidation. Within each melts step-test castings are made. The results of chemical composition analysis are presented and it changes in the various stages of melting have been determined. On the basis of microstructure analysis and simulation of casting solidification, the effect of cooling rate on the structure of the tested cast steel has been estimated.

12

Influence of the HPDL surface treatment of the X40CrMoV5-1 and 32CrMoV12-28 tool steels on wear resistance

Jonda E., Labisz K., Pakieła W.

Archives of Materials Science and Engineering

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2013

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Vol. 64, nr 2

152--159

EN

Purpose: This paper presents the results of laser remelting influence on structure and properties of the surface of the X40CrMoV5-1 and 32CrMoV12-28 hot work tool steels, carried out using the high power diode laser (HPDL). Structure changes were determined in the work, especially structure fragmentation. Also hardness investigation of the different remelting areas was performed. The purpose of this work was also to determine technological and technical parameters for a right performed HPDL remelting process. Boron nitride powder was used for alloying. The goal of this work was also to determine technical and technological conditions for remelting the surface layer with HPDL. Design/methodology/approach: Here are discusses the new methodology ways which can be applied in case of improving of the surface layer properties. A new laser treatment techniques applied in metal surface technology is here the most important feature. Also the influence of ceramic powders to the structure in all zones is investigated. Optical and scanning electron microscopy, EDS point wise and area microanalysis was used to characterize the microstructure and to investigate the intermetallic phases occurred. Findings: The most important factor is the zone structure of the surface layer which was coming into existence without cracks and defects as well as has a considerably higher hardness value compared to the non remelted material. It was find out, that the hardness of the alloyed surface layer increases according to the applied laser power. The highest power applied gives the highest hardness value in the remelted layer mostly in all user ceramic powders. Practical implications: The reason of this work was also to determine the laser treatment parameters, particularly the laser power, to achieve a good layer hardness for protection of this hot work tool steel from losing their work stability and to make the tool surface more resistant for work extreme conditions. The most important practical implication investigated in this work improves the appliance of HPDL laser for alloying and remelting of hot work tool steel. Originality/value: The originality of this work is assured through the using of an high-level up-to-date laser device for improvement of steel surface layer mechanical properties.

13

Effect of the remelting on transformations in Co-Cr-Mo prosthetics alloy

Kacprzyk B., Szymczak T., Gumienny G., Klimek L.

Archives of Foundry Engineering

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2013

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Vol. 13, iss. 3

47--50

EN

In the article we were studing the impact of the remelting on transformations in Co-Cr-Mo prosthetics alloy. The TDA curves were analyzed, the microstructure was examined, the analysis of the chemical composition and hardness using the Brinell method was made. It was found that the obtained microstructure of the alloys that we studied do not differ significantly. In all four samples, microscopic images were similar to each other. The volume, size and distribution of the phases remain similar. Analysis of the chemical composition showed that all the samples fall within the compositions provided for the test alloy. Further to this the hardness of the samples, regardless of the number of remeltings did not show any significant fluctuations and remained within the error limit. After analyzing all the results, it can be concluded that the remeltings of the alloys should not have a significant impact on their properties. Secondarily melted alloys can be used for prosthetics works.

14

Spawanie laserowe w naprawie napisu ARBEIT MACHT FREI z bramy głównej byłego obozu Auschwitz I

Turyk E., Ciepły M., Pęcherek M., Potrzebski M., Kuzio T., Czwórnóg B., Żydzik-Białek A., Bormann M., Jastrzębiowski A.

Przegląd Spawalnictwa

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2012

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R. 84, nr 3

37-40

PL

W artykule przedstawiono zastosowanie spawania laserowego w naprawie napisu ARBEIT MACHT FREI. Obejmowało ono wykonanie ściegów licowych w złączach doczołowych rur scalających konstrukcję napisu, spawanie naprawcze pęknięć w oryginalnych spoinach łączących litery z rurami, napawanie w celu odtworzenia pierwotnego kształtu spoin oraz miejscowe impulsowe przetapianie laserowe lica spoin naprawczych w celach dekoracyjnych.

EN

The paper presents application of the laser welding in repair of the ARBEIT MACHT FREI inscription. It included production of the face side runs in butt joints of tubes bonding the inscription structure, repair welding of fractures in the original welds joining letters with tubes, surfacing in order to reconstruct original shape of welds as well as laser spot impulse remelting of the weld faces for decoration purposes.

15

O tłumieniu drgań w materiałach kompozytowych

Pietrzak K., Klasik A., Makowska K., Sobczak J. J., Wojciechowski A., Rudnik D.

Prace Instytutu Odlewnictwa

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2012

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T. 52, z. 4

53-96

PL

Opracowanie dotyczy zdolności do tłumienia drgań kompozytów o osnowie stopu aluminium A359 zbrojonych 10%, 20% i 30% cząsteczek SiCp poddanych wielokrotnemu przetopowi. Celem badań było wykazanie, że recykling symulowany wielokrotnym przetopem nie zmienia istotnie charakterystyk tłumiących badanych materiałów. Na podstawie uzyskanych wyników można stwierdzić, że specyfika powierzchni międzyfazowej SiCp/ osnowa kompozytu stanowi główny czynnik wpływający na charakterystyki tłumiące kompozytów. Jednocześnie należy podkreślić, że właściwości powierzchni międzyfazowej SiCp/ osnowa kompozytu zależą od metody wytwarzania. Otrzymane wyniki potwierdzają potencjalne możliwości wprowadzenia do praktycznych rozwiązań przemysłowych recyklingu realizowanego prostą i ekonomicznie efektywną metodą wielokrotnego przetapiania. Należy jednak skupić wysiłki na minimalizacji porowatości gazowo-skurczowej podczas kolejnych procesów odlewania, aby nie dopuścić do pogorszenia charakterystyk mechanicznych.

EN

The study adresses the problem of the damping capacity of metal matrix composites based on A359 alloy reinforced with 10%, 20% and 30% SiCp, subjected to multiple remelting. The aim of the research was to prove that the recycling process simulated by multiple remelting does not significantly change the damping characteristics of the investigated materials. Based on the results obtained it was possible to ascertain that the specific character of the SiCp/ metal matrix interface is the main feature affecting the damping capacity of these materials. At the same time, it should be stressed that the properties of the SiCp/ metal matrix interface depend greatly on the manufacturing method. Strong bond produced between the reinforcing phase and composite matrix guarantees optimum mechanical characteristics at the expense of reduced damping capacity. The results confirm the potential possibilities of introducing to industrial practice the solution offered by the recycling process, which is a simple and economically effective method carried out by multiple remelting. However, efforts should focus on minimization of gas-shrinkage porosity during the successive casting operations to avoid the deterioration of mechanical characteristics.

16

Wpływ powtórnego przetapiania na właściwości mechaniczne i mikrostrukturę odlewniczego stopu kobaltu

Beer K., Walczak M., Surowska B., Borowicz J.

Inżynieria Materiałowa

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2012

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Vol. 33, nr 5

473--476

PL

Celem pracy było określenie wpływu powtórnego przetapiania na właściwości mechaniczne i mikrostrukturę odlewniczego stopu CoCrMo. Stop ten jest stosowany w protetyce dentystycznej do wykonywania protez szkieletowych. Ze względów ekonomicznych większość laboratoriów protetycznych korzysta z tzw. złomu metalowego jako części wsadu do produkcji. Złom ten mogą stanowić zarówno metale lub ich stopy, które były już raz użyte w procesie odlewania, jak i pozostałości po obróbce protetycznej. Doniesienia literaturowe wskazują, że taka praktyka może powodować zmianę właściwości mechanicznych i mikrostrukturalnych uzyskanych odlewów i wpływać na końcową jakość wyrobu. Doniesienia literaturowe wskazują na problem otrzymywania odmiennych wyników przez różnych autorów. Jako próbki do badań zastosowano jednokrotnie przetopiony stopu kobaltu o zawartości wyjściowej odpowiednio: 0, 25, 50, i 100% „materiału czystego” odlewany odśrodkowo. Wykonano badania wytrzymałości na rozciąganie i zginanie oraz pomiary makrotwardości. Została wykonana szczegółowa analiza mikrostrukturalna, jak również dokonano obserwacji przełomów powstałych po próbie rozciągania (rys. 3÷5). Stwierdzono pogorszenie właściwości mechanicznych wszystkich badanych stopów (rys. 1, tab. 1.) jak również nieznaczne zmiany twardości wszystkich badanych próbek (rys. 2). Zidentyfikowano fazy występujące w stopie. Zwrócono uwagę na obecność różnych typów węglików znajdujących się w mikrostrukturze odlewów (rys. 4). Zaobserwowano wzrost heterogeniczności mikrostruktury oraz gęstości mikropęknięć w objętości dendrytów badanych stopów ze zwiększeniem udziału materiau pochodzącego z recyklingu (rys. 5).

EN

The purpose of this paper was to establish the influence of remelting on the mechanical properties and microstructure of CoCrMo cast alloy. This alloy is used in prosthodontia to perform skeletal dentures. For economic reasons, most laboratories use the scrap metal as part of the production batch. This scrap may constitute either metals or their alloys, which were once already used in the casting process or the remains of the dental treatment. Literature reports indicate that this practice may cause a changes in microstructure and mechanical properties of obtained castings and affect the final quality of the product. This work was created as a response to the problem of getting different results by different researchers. As samples for research the castings from the cobalt alloy, using a disposable alloy with a starting output composition of 0, 25, 50, 75 and 100% of fine material respectively were used, and centrifugal casting method has been applied. The static tensile test, bonding test as well as macrohardness test have been conducted. Detailed microstructural as well as breakthroughs observations (Fig. 3÷5) after a tensile test have been carried out. The decrease of mechanical strength of all remelted alloys (Fig. 1, Tab. 1.) as well as insignificant hardness changes of all specimens were noticed (Fig. 2). The phase types occurring in the casting were identified. Particular attention was paid also to identify different types of carbides which were presented in microstructure of castings (Fig. 4). It was also observed a heterogeneity increase in the structure and density of microcracks in the volume of the dendrites of alloys with the addition of recycled material (Fig. 5).

17

The influence of remelting on the properties of AlSi6Cu4 alloy modified by antimony

Medlen D., Bolibruchova D.

Archives of Foundry Engineering

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2012

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Vol. 12, iss. 1

81-86

EN

The paper deals with the problem of multiple remelting influence on AlSi6Cu4 alloy modified by antimony on chosen mechanical characteristics, microstructure and gas content. This foundry alloy is used mostly in automotive industry. Foundry Aluminum-Silicon alloys are also used in number of industrial weight sensitive applications because of their low weight and very good castability and good mechanical properties. Modifiers are usually added to molten aluminum-silicon alloys to refine the eutectic phase particle shape and improve the mechanical properties of the final cast products and Al-Si alloys cast properties.

18

Structure of X5CrNi18-10 and S355NL steels after remelting with the electric arc

Adamiak S.

Archives of Foundry Engineering

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2012

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Vol. 12, iss. 2

139-142

EN

The work presents the results of the research and tests of the surface machining of the S355NL and X5CrNi18-10 steels with the concentraded stream of heat with the usage of the GTAW method. The surface layers of the tested steels were remelted with the electric arc using the current of the electric arc 50, 100, 150 and 200A.The machining was done in the atmosphere of argon with the constant speed of the welding head. A microscope examination was performed of the obtained structure and measurements of depth, width and hardness of the received surface layer were performed. Moreover the relation between the current of the electric arc and geometry of the remelted layers with their microhardeness was examined.

19

HPDL Remelting of Anodised Al-Si-Cu Cast Alloys Surfaces

Labisz K., Tański T., Janicki D.

Archives of Foundry Engineering

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2012

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Vol. 12, iss. 2s

45--48

EN

The results of the investigations of the laser remelting of the AlSi9Cu4 cast aluminium alloy with the anodised and non-anodised surface layer and hardness changes have been presented in this paper. The surface layer of the tested aluminium samples was remelted with the laser of a continuous work. The power density was from 8,17•103 W/cm2 to 1,63•104 W/cm2. The metallographic tests were conducted in form of light microscope investigations of the received surface layer. The main goal of the investigation was to find the relation between the laser beam power and its power density falling on a material, evaluating the shape and geometry of the remelted layers and their hardness. As the substrate material two types of surfaces of the casted AlSi9Cu4 alloy were applied – the non–treated as cast surface as well the anodized surface. As a device for this type of surface laser treatment the High Power Diode Laser was applied with a maximum power of 2.2 kW and the dimensions of the laser beam focus of 1.8 x 6.8 mm. By mind of such treatment it is also possible to increase hardness as well eliminate porosity and develop metallurgical bonding at the coating-substrate interface. Suitable operating conditions for HPDL laser treatment were finally determined, ranging from 1.0 to 2.0 kW. Under such conditions, taking into account the absorption value, the effects of laser remelting on the surface shape and roughness were studied. The results show that surface roughness is reduced with increasing laser power by the remelting process only for the non-anodised samples, and high porosity can be found in the with high power remelted areas. The laser influence increases with the heat input of the laser processing as well with the anodisation of the surface, because of the absorption enhancement ensured through the obtained alumina layer.

20

Define the type of tribological wear of high speed steel remelted with the electric arc with the usage of the confocal microscope

Dziedzic A.

Archives of Foundry Engineering

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2012

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Vol. 12, iss. 2

153-158

EN

The paper presents the possibility of the usage of the concfocal microscope for define the type of tribological wear present during the technical dry friction on the testing machine of the pin-on-disc T-01M. The pin was a remelted high-speed steel and the disc was made from sintered carbides. The surface layer of the high-speed steel was remelted with the electric arc with different parameters. The intensity of the electric arc current was changed, the scanning speed and the single, overlapping remeltings were used. On the basis of the 3D, 2D view of the surface friction of the pin (made from the remelted high-speed steel), disc (made from the sintered carbides) and the surface roughness profile run along the marked line, the presence of the abrasive wear can be defined with the description of the elementary wear processes due to the abrasive and/or adhesive wear.