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1

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.

2

Influence of ageing on microstructure and mechanical properties of TP347HFG austenitic stainless steel

Golański Grzegorz, Purzyńska Hanna

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 2

art. no. e144607

EN

The paper presents the results of microstructural and mechanical investigation of long-term aged TP347HFG austenitic stainless steel. Ageing was performed at a time of up to 30 000 hours and the temperature of 600 and 650◦C. Ageing was proved to lead to the precipitation of secondary phase particles not only inside grains but also on the boundaries of grains and twins. The MX precipitates were observed inside the grains. However, M23C6 carbides and sigma phase precipitates were observed on grain boundaries. The changes in the microstructure of the examined steel translated into the mechanical properties, i.e. initially observed growth and then the decrease of yield strength and a gradual decrease in impact energy. The overageing process – a decrease in strength properties – was associated with the growth of the size of M23C6 carbides and the precipitation of the sigma phase. The reduction of impact energy in TP347HFG austenitic stainless steel was found to be associated with the precipitation of M23C6 carbides in the case of the 600◦C temperature, and the M23C6 carbides and sigma phase in the case of the 650◦C temperature. The rate of changes in the microstructure and mechanical properties depended on the ageing temperature.

3

The effect of the TIG method-based melting of welds on the properties and the structure of welded joints made of austenitic steel

Cyprian Tyszko, Jacek Górka

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2022

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Vol. 66, No. 1

43--49

EN

The article discusses the effect of TIG method-based melting on the properties and the structure of welded joints made of austenitic steel AISI 304. The tests involved the making of 2 mm thick joints and their subsequent melting in two different ways, i.e. with maintaining interpass temperature and immediately after welding. The study also included the performance of mechanical tests, macro and microscopic metallographic tests as well as hardness and corrosion resistance tests. Results obtained in the tests justified the conclusion that the melting process and its conditions significantly affect the properties and the structure of welded joints.

PL

W niniejszym artykule zbadano wpływ przetapiania spoiny metodą TIG na własności oraz strukturę złączy spawanych stali austenitycznej X5CrNi18-10. W tym celu wykonano złącza próbne blach o grubości 2 mm, a następnie poddano je przetopieniu na dwa różne sposoby, tj. z zachowaniem temperatury międzyściegowej oraz bezpośrednio po spawaniu. Następnie przeprowadzono badania wytrzymałościowe, metalograficzne makro- i mikroskopowe, pomiary twardości oraz badania odporności korozyjnej. Na ich podstawie oceniono, że przetopienie oraz jego warunki w znacznym stopniu wpływają na własności i strukturę złącza spawanego.

4

Cold unidirectional/cross‑rolling of austenitic stainless steels: a review

Mohammadzehi Sara, Mirzadeh Hamed

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 3

art. no. e129

EN

The effects of cold unidirectional/cross-rolling on the development of substructure, strain-induced martensitic transformation, crystallographic texture (preferred orientation), and mechanical properties, as well as the microstructure after subsequent annealing of metastable austenitic stainless steels were overviewed. First, the deformed state was discussed. Compared to unidirectional rolling, it was revealed that cross-rolling leads to the formation of a greater amount of deformation-induced martensite, which is related to the generation of numerous intersecting shear bands and nano-twins, as well as a higher dislocation density in the austenite phase (activation of higher number of slip/twinning systems). It was concluded that these effects are more pronounced at low reductions in thickness. Regarding texture evolution, cross-rolling tends to strengthen the Brass component in the retained austenite phase. Subsequently, the mechanical properties were reviewed, where it was concluded that a more rapid work-hardening and higher strength/hardness at low strains can be obtained due to the effects of cross-rolling on the microstructure. Moreover, while the effects of cross-rolling on the strength at high rolling reductions might not be significant, it is possible to decrease the anisotropy of the sheet due to the alternate change in the rolling direction. Afterward, the annealing of cold-rolled sheets was discussed. It was deduced that cross-rolling might be used for more intense grain refinement based on the thermomechanical processing of cold-rolling and reversion/recrystallization annealing, where the activation of greater number of slip systems, higher dislocation density, and greater martensite content in the deformed state are responsible in this regard. Finally, the suggestions for future works were proposed.

5

Corrosion behavior of Cr-Ni-Mo stainless steel in chemically modified chloride solution

Zatkalíková Viera, Markovičová Lenka, Štrbák Milan

Quality Production Improvement - QPI

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2021

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Vol. 3, Iss. 1

299--304

EN

Cr-Ni-Mo stainless steels are susceptible to the pitting in aggressive chloride environments. One of the possible ways for the influence of their corrosion behavior is the use of inhibitors as the chemical modification of the environment. The resistance of AISI 316Ti stainless steel to the pitting with/without the inorganic inhibitor was tested by two independent corrosion tests: 24-hours exposure immersion and potentiodynamic polarization test. Both tests were carried out in 1M chloride acidic solution with/without 0.1M molybdate inhibitor at room temperature. Results of immersion tests were evaluated by the corrosion rates calculated from corrosion losses and by the morphology of the pitting. Potentiodynamic polarization curves were evaluated by the pitting potentials.

6

Odporność na korozję austenitycznej stali nierdzewnej poddanej chemicznej obróbce w różnych temperaturach

Zatkalíková Viera, Iwaniak Aleksander, Markovičová Lenka, Uhríčik Milan, Hanusová Patrícia

Przemysł Chemiczny

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2020

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T. 99, nr 6

844--847

PL

Austenityczna stal nierdzewna jest uważana za materiał o doskonałej odporności na korozję i akceptowalnych właściwościach mechanicznych, zalecany do różnych zastosowań konstrukcyjnych, przemysłowych i biomedycznych. W agresywnych środowiskach chlorkowych jest ona podatna na miejscową korozję wżerową. Oceniono odporność na korozję stali nierdzewnej typu AISI 316Ti o powierzchni pasywowanej kwasem azotowym w kwasowym 1 M roztworze jonów chlorkowych w temp. 22-80°C. Ocenę tę oparto na wynikach ekspozycyjnych testów zanurzeniowych i wynikach elektrochemicznej spektroskopii impedancyjnej (EIS).

EN

Com. Ti-stabilized Cr-Ni-Mo austenitic stainless steel was passivated with HNO₃ soln. and then studied for pitting corrosion in 5% FeCl₃ soln. (pH 1.2) by 24-hours std. immersion test and in 0.9 M NaCl + 0.1 M HCl soln. (pH 1.1) by electrochem. impedance spectroscopy (EIS test) at 22- 80°C. The pits were significantly bigger at 22°C than those at 50°C but the distribution of pitting was markedly lower. The polarization resistance decreased with increasing the temp. The quality of the surface passive film was several times lower at 80°C than at the lower temp.

7

A novel deep penetrating eddy current probe based on phase shifted fields and its application to inspection of defects

Wu Meixian, Zhang Dongli, Wang Chuanglong

Metrology and Measurement Systems

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2020

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Vol. 27, nr 2

275--287

EN

Due to the skin effect of eddy currents, the depth of cracks which can be detected by the traditional eddy current probe is very limited. In order to improve the ability of eddy current probes to inspect deep cracks in metal thick-walled structures, a new eddy current probe using an excitation system with phase shifted fields was proposed. Its feasibility for detecting deep cracks was verified by simulation and experiments. The results showed that the penetration depth of eddy currents in austenitic stainless steel is effectively enhanced by using the new probe.

8

CO2 laser spot welding of thin sheets AISI 321 austenitic stainless steel

Shehab A. A., Nawi S. A., Al-Rubaiy A. AAG, Hammoudi Z., Hafedh S. A., Abass M. H., Alali M. S., Ali S. D.

Archives of Materials Science and Engineering

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2020

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Vol. 106, nr 2

68--77

EN

Purpose: The present work aims to investigate the influence of CO2 laser spot welding (LSW) parameters on welding profile and mechanical properties of lap joint of AISI 321 thin sheet metals, and analyze the welding profile numerically by finite element (FE) method. Design/methodology/approach: The weld carried out using 150 W CO2 continues wave laser system. The impact of exposure time and laser power on the welding profile was investigated using an optical microscope. Microhardness and tensile strength tests were used to evaluate the mechanical properties of the joint. Ansys software was utilized to simulate the welding profile numerically. Findings: The results revealed that 2 s exposure time and 50 W power have led to uniform welding profile and highest shear force (340 N), lower hardness gradient across the heat affected zone (HAZ) and fusion zone (FZ). Finite element (FE) analysis of the welding profile showed good agreement with experimental analysis. Research limitations/implications: The selection of laser spot welding parameters for thin sheet metal was critical due to the probability of metal vaporisation with extra heat input during welding. Practical implications: Laser welding of AISI 321 steel is used in multiple industrial sectors such as power plants, petroleum refinement stations, pharmaceutical industry, and households. Thus, selecting the best welding parameters ensures high-quality joint. Originality/value: The use of CO2 laser in continuous wave (CW) mode instead of pulse mode for spot welding of thin sheet metal of AISI 321 austenitic stainless steel consider a real challenge because of the difficulty of control the heat input via proper selection of the welding parameters in order to not burn the processed target. Besides, the maintenance is easier and operation cost is lower in continuous CO2 than pulse mode.

9

Microstructure, mechanical properties and corrosion behavior of austenitic stainless steel sheet joints welded by gas tungsten arc (GTA) and ultrasonic–wave–assisted gas tungsten pulsed arc (U–GTPA)

Xie Weifeng, Yang Chunli

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 2

177--190

EN

Here, ultrasonic–wave–assisted gas tungsten pulsed arc (U–GTPA) welding is proposed as a new alternative welding process to gas tungsten arc (GTA) welding. To better understand the advantages of this new process, in this paper, the microstructure, mechanical properties and corrosion behavior of GTA- and U–GTPA-welded joints of 316L stainless steel are systematically compared. These results show that the weld zone (WZ) depth-to-width ratio of the U–GTPA-welded joint increased, and the area of the equiaxed grain zone was larger than that of the GTA-welded joint. This results in finally increasing the strength and hardness for U–GTPA-welded joints, and the ultimate tensile strength and elongation of the U–GTPA-welded joints were 7.1% and 26.2% greater than those of the GTA-welded joint, respectively. For the U–GTPA-welded joint, under the action of the pulsed arc, the grain distribution with high-angle boundaries (HABs) was different from that of the GTA-welded joint. The minimum of the HAB fraction corresponded to the fracture position for both joints in tensile tests. It shows that a large number of HABs were beneficial in improving joint tensile properties. However, for electrochemical corrosion experiments of two WZs in 3.5% NaCl solution, despite this GTA WZ having a higher HAB fraction, the corrosion current density and corrosion potential of U–GTA WZ were lower and higher than those of the GTA WZ, respectively. The corrosion rate and corrosion sensitivity of U–GTPA WZ indicated good corrosion resistance.

10

Corrosion properties of 1.4512 ferritic and 1.4404 austenitic steels for the automotive industry

Zatkalíková Viera, Markovičová Lenka, Wróbel-Knysak Anna

System Safety : Human - Technical Facility - Environment

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2019

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Vol. 1, nr 1

745--752

EN

Exhaust systems are susceptible to in-service wear because of their exposition to the very aggressive corrosive environment. Various stainless steels grades (mostly ferritic and austenitic, but also martensitic and duplex) and protective coatings are currently used for exhaust system elements to increase their aestetics and corrosion resistance. This article focuses on evaluation and comparison of the common corrosion properties of two stainless steels with different microstructures (ferritic and austenitic) used for exhaust system components at the low ambient temperature (35 °C). An aggressive acidic corrosion solution for electrochemical cyclic potentiodynamic tests (ASTM G61) was chosen to simulate partly inner (condensate) and also external environment (reaction of exhaust gases with water, chlorides in solution after winter road maintenance). Exposure tests of the pitting corrosion resistance were performed according to ASTM G48 standard method.

11

Local corrosion of AISI 304 stainless steel in acidic chloride solution

Zatkalíková Viera, Markovičová Lenka, Hanusová Patrícia

Quality Production Improvement - QPI

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2019

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Vol. 1, Iss. 1

268--275

EN

AISI 304 austenitic stainless steel is recommended and used for various applications in industry, architecture and medicine. Presence of halides in environment evokes a possibility of the local corrosion which limits seriously exploitation of this material in aggressive conditions. The presented paper is focused on the pitting corrosion resistance (“as received” steel surface) in 1M chloride solution (pH=1.2) at a common (20 °C) and an elevated (50 °C) ambient temperatures. 24-hours exposure immersion test (ASTM G48) and cyclic potentiodynamic test (ASTM G61) are used as the independent test methods. The exposure immersion test is carried out with cross-rolled and longitudinally rolled specimens and the effect of direction of rolling on the resistance to pitting is studied.

12

Study of Technology for Ultrafine-Grained Materials for Usage as Materials in Nuclear Power

Naizabekov Abdrakhman, Arbuz Alexandr, Lezhnev Sergey, Panin Evgeniy, Knapiński Marcin

New Trends in Production Engineering

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2019

|

Vol. 2, Iss. 2

114-125

EN

Nuclear power is associated with great environmental risks. In many cases, the problem of accidents of nuclear power plants is related to the use of materials that do not fully meet the following requirements: high corrosion resistance; high temperature resistance; creep resistance; fracture toughness; stability of structure and properties under irradiation. Therefore, studies aimed at finding materials that can withstand long-term loads at high temperatures, aggressive environment and gradual structural degradation under the influence of radiation are relevant. One of the structural materials, which has high resistance to radiation, is austenitic stainless steel. And one of the ways to increase the radiation resistance of parts made of this steel grade is to grind its microstructure to ultra-fine-grained state. Such structures provide a combination of a high level of strength characteristics with high plasticity, which distinguishes such materials from their coarse-grained counterparts. Also, numerous grain boundaries serve as runoff surfaces for radiation defects, preserving the structure, which causes their increased radiation resistance. From all methods for producing sub-ultra-fine grained materials the most promising is the severe plastic deformation (SPD), which can be implemented in the metal in various ways, including radial-shear rolling. This paper presents the results of studies of the process of radial-shear rolling on the mill SVP-08 and its effect on the microstructure and properties of austenitic stainless steel. During the study, bars with a diameter of 13 mm from AISI-321 steel with a grain size of 300-600 nm were obtained, while the mechanical properties increased more than 2 times compared to the initial values.

13

The influence of total gas pressure and atmosphere composition during ion cleaning step on S-phase coating formation

Słowik Justyna, Fryska Sebstian, Baranowska Jolanta

Inżynieria Materiałowa

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2019

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Vol. 40, nr 1

2--8

EN

Various ion sputtering parameters were applied prior to the deposition of S phase coatings in order to determine their effect on the efficiency of cleaning an austenitic steel surface. For this purpose, two types of atmospheres were used (100% Ar and 5% Ar + 95% H2) at two different pressures (1.33 Pa and 2.67 Pa). In addition, substrates with two different initial states — without polishing and with polishing — were investigated. The thickness of the diffusion layer, obtained in the austenitic substrate after depositing an S-phase coating by magnetron sputtering, was used as a measure of the surface cleaning effectiveness (passive oxide layer removal). The research showed that all the considered parameters had a significant effect on the effectiveness of the cleaning treatment. It was found that the initial state of the substrate has an influence on the thickness of the diffusion layers, with thicker layers obtained on nonpolished substrates. The total gas pressure affects the substrate cleaning effectiveness in different ways depending on the gas composition used. It is possible that a physical sputtering mechanism occurs in the case of argon and a chemical reduction mechanism in the case of hydrogen. In addition, it was found that the degree of surface cleaning determines the texture of the S phase coatings.

PL

Faza S, uznawana za przesycony roztwór azotu w austenicie, może być otrzymywana nie tylko wskutek konwencjonalnego azotowania, lecz także metodą reaktywnego rozpylania magnetronowego stali austenitycznej w atmosferze azotu. Wytworzenie takiej powłoki na stali austenitycznej poprawia jej twardość i odporność na zużycie tribologiczne. Przed procesem napylania stosuje się zwykle oczyszczanie jonowe, które w przypadku stali austenitycznej może prowadzić do usunięcia warstwy pasywnej tlenków. W ten sposób jest możliwe powstanie warstwy dyfuzyjnej w podłożu w efekcie dyfuzji azotu z powłoki do podłoża. Stanowi ona gradientową międzywarstwę potencjalnie korzystną z punktu widzenia poprawy adhezji. Celem pracy było zbadanie wpływu parametrów oczyszczania jonowego stosowanego przed reaktywnym osadzaniem powłok z fazy S na wytworzenie warstwy dyfuzyjnej w podłożu ze stali austenitycznej.

14

In situ investigations of microstructural changes during tensile deformation of AISI 304L stainless steels

Singh Navjot, Nanda Tarun, Kumar B. Ravi, Das Swapan Kumar, Singh Vishal

Archives of Civil and Mechanical Engineering

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2019

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Vol. 19, no. 3

672--679

EN

The present work investigates the microstructural changes in an AISI 304L austenitic stainless steel during the early stages of tensile deformation (where austenite does not transform to strain induced martensite). In situ tensile experiments were conducted to record grain orientation changes and slip activation in the steel. The effect of grain size, neighboring grains, and annealing twins on orientation changes during deformation was investigated. Results showed that at a given strain level, grains lying in relatively softer regions and possessing higher Schmid factor values accommodated the plastic deformation initially and showed orientation changes toward the stable orientation. The relatively larger grains changed their orientations only at higher strain levels. Grain orientation changes were also influenced by size and crystallographic orientation of neighboring grains. For grains containing annealing twins, the orientation changes of twin and its grain were in different directions during deformation at a given strain level. Further, grains containing multiple twins showed delayed deformation. The study of tensile deformation behavior in this respect opens up new routes to alter and hence enhance the mechanical properties of materials by engineering their microstructure.

15

Corrosion Resistance of X5CrNi18-10 Stainless Steel

Kciuk M., Lasok S.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 4

2101--2106

EN

The paper presents the influence of heat treatment on the structure and corrosion resistance of X5CrNi18-10 steel. To determine the structure which has been obtained after heat treatment the methods of light and scanning electron microscopy with EDS microanalysis were used. The electrochemical corrosion properties of the investigated steel were studied in 3.5% NaCl solution using potentiodynamic polarization tests. Basing on the registered curves, the corrosion current, polarization resistance and corrosion potential were determined. The corrosion tests were followed by fractographic researches.

16

Comparison of Vacuum Sintered and Selective Laser Melted Steel AISI 316L

Brytan Z.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 4

2125--2131

EN

The paper presents the results of the basic mechanical properties determined in the static tensile test, impact un-notched Charpy test and hardness of austenitic stainless steel type 316L produced by two techniques: classical pressing and sintering in a vacuum with rapid cooling and selective laser melting (SLM). In this work fracture surface of Charpy test, samples were studied. The results indicate that application of selective laser melting (SLM) makes it possible to double increase the strength properties of components manufactured from austenitic stainless steel type 316L compared to sintering in a vacuum. Resulted in mechanical properties strongly depend on porosity characteristic and the presence of superficial oxides in the case of sintered steel and the character of observed microstructural defects deriving from non-fully melted powder particles and the formation of voids between subsequently melted pool tracks during the SLM.

17

Special marine steels and constructional-ballistic shields designed PNA

Zatorski Z.

Zeszyty Naukowe Akademii Marynarki Wojennej

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2016

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R. 57 nr 3 (206)

131--145

EN

In order to increase security of the country in the field of new materials and technologies and research methods were developed, patented and implemented: austenitic steel X02CrNiMoMnN21-16-5-4 with electrodes for welding of steel and high-strength bainitic steel 10GHMBA-E620T. The author developed a theoretical and technological basis for the design of marine constructional-ballistic shields, which has implemented a pilot scale and technical support. In addition, he developed an original method for testing ballistic shields and unified position to the research, which studied and co-patented.

PL

Dla wzrostu bezpieczeństwa kraju w zakresie nowych materiałów i technologii oraz metod badawczych opracowano, opatentowano i wdrożono: stal austenityczną X02CrNiMoMnN21-16-5-4 wraz z elektrodami do spawania tej stali oraz wysokowytrzymałą stal bainityczną gat. 10GHMBA-E620T. Autor opracował teoretyczne i technologiczne podstawy projektowania okrętowych osłon konstrukcyjno-balistycznych, które wdrożył w skali półtechnicznej i technicznej. Ponadto opracował oryginalną metodę badania odporności balistycznej osłon oraz zunifikowane stanowisko do badań, które przebadał i współopatentował.

18

Korozja stali odpornych na korozję w środowiskach wodnych i profilaktyka antykorozyjna

Marjanowski J.

Dozór Techniczny

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2016

|

z. 1

14--20

19

Influence of nitriding and laser remelting on properties of austenitic stainless steel type X10CrNi18-8 and cavitation erosion resistance

Sitko A., Szkodo M., Kucharski S.

Advances in Materials Science

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2016

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Vol. 16, nr 2(48)

21--31

EN

The paper presents properties of surface layers. Surface layers were obtained by using low temperature glow–discharge nitriding process and laser remelting carried out on austenitic stainless steel type X10CrNi18-8. Investigations were done by using an Ultra Nanoindentation Tester (UNHT) in the Warsaw Institute of Fundamental Technological Research. The influence of the above mentioned treatments on obtained surface layers is shown. The values of the Vickers hardness (HV), the irreversible indentation work (Wir), the reversible work (We) and the maximum depth (hmax) during indentation were determined using the method proposed by Oliver and Pharr [1]. On the basis of mechanical properties, the elasticity (Ie) and ductility (Iir) indexes were calculated. Moreover, microstructure cross-section of the austenitic stainless steel after nitriding process and laser remelting was observed using a scanning electron microscope. Cavitation test was performed at a vibratory rig with stationary specimen. On the basis of erosion curves the cavitation resistance was evaluated.

20

Wpływ kulowania na właściwości użytkowe połączeń spawanych stali austenitycznej 1.4539 wykonanych metodą TIG i wiązką lasera

Nasiłowska B., Bogdanowicz Z., Mońka G., Szymański W.

Przegląd Spawalnictwa

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2015

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R. 87, nr 3

36--39

PL

W pracy przedstawiono wpływ kulowania pneumatycznego powierzchni na strukturę, mikrotwardość i naprężenia własne połączeń wykonanych ze stali austenitycznej 1.4539 spawanej wiązką lasera CO2 i metodą TIG. Celem praktycznym badań było uzupełnienie obecnego stanu wiedzy dotyczącego połączeń spawanych laserowo i metodą TIG umocnionych kulowaniem powierzchni. Badania wykazały znaczne rozdrobnienie struktury powierzchni połączeń spawanych oraz wzrost mikrotwardości i naprężeń ściskających.

EN

This article presents shot-peening effect on the structure, microhardness and compressive of the austenitic steel 1.4539 welded by TIG and CO2 laser beam. Practical research aim is to supplement current state of knowledge and practice of the welded joints of the austenitic steel 1.4539 made by TIG and laser beam which is reinforced by shot-peening. The research shows significant defragmentation of the welded connections structure, microhardness and compressive stress increase.