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DEVELOPMENT OF CHROMATE-FREE PASSIVATION PROCESSES FOR MAGNESIUM ALLOY AZ31B az31b镁合金无铬钝化工艺的发展
METAL 2020 Conference Proeedings Pub Date : 2020-01-01 DOI: 10.37904/metal.2020.3550
M. Šimonová, A. Abrashov, N. Grigoryan, T. Vagramyan, V. Men'shikov
{"title":"DEVELOPMENT OF CHROMATE-FREE PASSIVATION PROCESSES FOR MAGNESIUM ALLOY AZ31B","authors":"M. Šimonová, A. Abrashov, N. Grigoryan, T. Vagramyan, V. Men'shikov","doi":"10.37904/metal.2020.3550","DOIUrl":"https://doi.org/10.37904/metal.2020.3550","url":null,"abstract":"The disadvantage of magnesium alloys is their low corrosion resistance due to high electronegativity. One of the most effective methods to improve the corrosion resistance of magnesium alloys is to form a conversion adhesive coating on their surface, followed by applying paintwork materials. Chromatic coatings are widely used as adhesion layers under the paintwork before staining magnesium and its alloys. In recent years, in world practice, as an alternative to chromate layers on magnesium and its alloys, nanoscale conversion titanand/or zirconiumcontaining, and cerium-containing adhesive coatings have been used. The present work is devoted to the development of the technology for producing these coatings. It has been established that the developed passivating coatings based on the AZ31B magnesium alloy are comparable with chromate coatings in terms of corrosion resistance and protective ability. It has been established that coatings with developed adhesive sublayers have a higher adhesion strength to the base compared to coatings with chromate adhesive sublayer.","PeriodicalId":18449,"journal":{"name":"METAL 2020 Conference Proeedings","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86183863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
AUTOMATION OF THE SHIPPING PROCESS OF METALLURGICAL PRODUCTS 冶金产品运输过程的自动化
METAL 2020 Conference Proeedings Pub Date : 2020-01-01 DOI: 10.37904/metal.2020.3639
Tomáš Kutáč, Josef Kutáč, E. Švecová
{"title":"AUTOMATION OF THE SHIPPING PROCESS OF METALLURGICAL PRODUCTS","authors":"Tomáš Kutáč, Josef Kutáč, E. Švecová","doi":"10.37904/metal.2020.3639","DOIUrl":"https://doi.org/10.37904/metal.2020.3639","url":null,"abstract":"This article explores the options for automating the process involved in shipping metallurgical products. The shipping process usually begins with the logistics team entering a request for shipping into the information system after production is complete. The team then searches for a contracted transport company, selects the least expensive from the available options, creates an order in the system, contacts the selected company, and before commencing with shipment, enters the vehicle and driver information into the system. Under the desired solution, this entire process would be automated with a web application, with only the driver and vehicle information being entered by the transport company.","PeriodicalId":18449,"journal":{"name":"METAL 2020 Conference Proeedings","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82111618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Improving performance and service life of Rail vehicles components by twin wire arc spraying 采用双线电弧喷涂技术提高轨道车辆部件的性能和使用寿命
METAL 2020 Conference Proeedings Pub Date : 2020-01-01 DOI: 10.37904/metal.2020.3570
P. Šulcová, M. Vostřák, J. Antoš, K. Lencová
{"title":"Improving performance and service life of Rail vehicles components by twin wire arc spraying","authors":"P. Šulcová, M. Vostřák, J. Antoš, K. Lencová","doi":"10.37904/metal.2020.3570","DOIUrl":"https://doi.org/10.37904/metal.2020.3570","url":null,"abstract":"The components of rail vehicles are strained by a number of sources, whether operational, natural, or effects caused by passengers. For protection against these influences, the number of types of surface protection is frequently used. The project called “Increasing of resistance of rail vehicles components by the means of modern thermal spraying technologies” deals with improving the performance and service life of rail vehicle components by thermal spraying. In the project, more than ten components are selected for coating by different material sprayed by different methods of thermal spraying. This paper is focused on coating made by Twin Wire Arc Spraying. Three materials of coating sprayed by TWAS were tested and their mechanical properties were evaluated in this paper. These materials are pure molybdenum, Fe13Cr, and Zn15Al. The Ball on Flat, Dry Sand/Rubber wheel Test, and Erosion Wear Resistance Test were done. The molybdenum coating showed very good sliding properties. This material can find its application for rolling components such as rollers, or rollers carriers. The Fe13Cr and Zn15Al coatings showed a very good erosion resistance. The Zn15Al had even a better erosion resistance than Fe13Cr. Both of these materials can be used, where this type of wear resistance is required, for example for walkable footplates. The Fe13Cr had also a very good abrasive resistance in contrast with Zn15Al, which can’t be recommended for application where abrasion resistance is required. The spraying of real components is also shortly presented in this paper.","PeriodicalId":18449,"journal":{"name":"METAL 2020 Conference Proeedings","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83068545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Microstructure, Tribological Behaviour and xrd analysis of HVOF Sprayed and Laser Remelted CoCrTaAlCSiY Coatings HVOF喷涂和激光重熔CoCrTaAlCSiY涂层的微观结构、摩擦学性能和xrd分析
METAL 2020 Conference Proeedings Pub Date : 2020-01-01 DOI: 10.37904/metal.2020.3539
A. Glanc, Š. Houdková, Z. Jansa, M. Vostřák
{"title":"Microstructure, Tribological Behaviour and xrd analysis of HVOF Sprayed and Laser Remelted CoCrTaAlCSiY Coatings","authors":"A. Glanc, Š. Houdková, Z. Jansa, M. Vostřák","doi":"10.37904/metal.2020.3539","DOIUrl":"https://doi.org/10.37904/metal.2020.3539","url":null,"abstract":"Superalloys with cobalt as a base material are widely used among different industry applications. Their main advantages are excellent corrosion and wear resistance. Material CoCrTaAlCSiY was chosen for this study as an unexplored representative of Co-based superalloys with a potential for good tribological behavior. This paper follows the results of previous paper called “Microstructure and Tribological Behavior of HVOF Sprayed and Laser Remelted CoCrTaAlCSiY Coatings”. In this paper are also presented three states of HVOF sprayed and post laser treated coatings of CoCrTaAlCSiY (as spray state and two different laser treatments varying in specific energy of laser). Pin-on-disc test was carried out to evaluate wear behavior. XRD analysis was done to reveal phase transformations between FCC and HCP. A positive effect on wear coefficient for both laser treated CoCrTaAlCSiY coatings was proved.","PeriodicalId":18449,"journal":{"name":"METAL 2020 Conference Proeedings","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81983913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Microstructure and mechanical properties of TiAl-based alloy produced by selective laser melting 选择性激光熔化制备tial基合金的显微组织和力学性能
METAL 2020 Conference Proeedings Pub Date : 2020-01-01 DOI: 10.37904/metal.2020.3604
I. Polozov, Artem Kantyukov, V. Popovich, Jia-Ning Zhu, A. Popovich
{"title":"Microstructure and mechanical properties of TiAl-based alloy produced by selective laser melting","authors":"I. Polozov, Artem Kantyukov, V. Popovich, Jia-Ning Zhu, A. Popovich","doi":"10.37904/metal.2020.3604","DOIUrl":"https://doi.org/10.37904/metal.2020.3604","url":null,"abstract":"Additive Manufacturing (AM) is an attractive way of producing parts of intermetallic titanium alloys. However, high brittleness of these alloys makes it challenging to produce crack-free intermetallic parts by AM. One way to overcome this problem is to use high-temperature powder-bed preheating. In this paper, Ti-48Al-2Cr-2Nb alloy was obtained by selective laser melting process with high-temperature preheating of 800-900 ºC. Crack-free specimens with a relative density of 99.9% were fabricated using an optimized process parameter set. Microstructure and phase composition were studied using scanning electron microscopy and X-Ray diffraction to reveal a fine microstructure consisting of lamellar α2/γ colonies, equiaxed γ grains, and retained β phase. Compressive tests and microhardness measurements showed that the produced alloy exhibited superior properties compared to the conventionally obtained TiAl-alloy. reports the results of the investigation of L-PBF process using Ti-48Al-2Cr-2Nb alloy powder with an inductive high-temperature platform preheating. The effects of L-PBF process parameters and preheating temperature on fabricated TiAl-alloy microstructure and mechanical properties are investigated.","PeriodicalId":18449,"journal":{"name":"METAL 2020 Conference Proeedings","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89655736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 4
EFFECT OF STRAIN ACCUMULATION UNDER HIGH TEMPERATURE THERMOMECHANICAL PROCESSING ON THE ROLLING FORCE AND MECHANICAL PROPERTIES OF AUSTENITIC STAINLESS STEEL WITH VARIOUS CARBON CONTENT 高温热机械加工中应变积累对不同含碳量奥氏体不锈钢轧制力和力学性能的影响
METAL 2020 Conference Proeedings Pub Date : 2020-01-01 DOI: 10.37904/metal.2020.3468
A. Rudskoi, G. Kodzhaspirov, J. Kliber
{"title":"EFFECT OF STRAIN ACCUMULATION UNDER HIGH TEMPERATURE THERMOMECHANICAL PROCESSING ON THE ROLLING FORCE AND MECHANICAL PROPERTIES OF AUSTENITIC STAINLESS STEEL WITH VARIOUS CARBON CONTENT","authors":"A. Rudskoi, G. Kodzhaspirov, J. Kliber","doi":"10.37904/metal.2020.3468","DOIUrl":"https://doi.org/10.37904/metal.2020.3468","url":null,"abstract":"The effect of the strain accumulation by changing the number of rolling passes on the rolling force, structure and mechanical properties of austenitic Cr-Ni-Ti stainless steel with different carbon contents has been studied. An increase of the number of passes for a given overall reduction was found to have a beneficial effect on tensile properties while maintaining adequate ductility. At a rolling temperature of 1100 - 1150 °C with rolling in 1-3 passes, an increase in carbon content leads to acceleration of softening processes. With a lower rolling temperature and an increased number of passes, the reverse effect is obtained. When working out rolling schedules for sequences in HTMP conditions involving cooling before the final passes, residual hardening must be taken into account in rolling force calculations to prevent to prevent the mechanical equipment of the rolling stand from the breakage.","PeriodicalId":18449,"journal":{"name":"METAL 2020 Conference Proeedings","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89076098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
SMALL PUNCH TESTING OF THICK WALLED PIPE MADE OF THE STEEL P92 WITH HETEROGENEOUS MICROSTRUCTURE 非均匀组织p92钢厚壁管的小冲孔试验
METAL 2020 Conference Proeedings Pub Date : 2020-01-01 DOI: 10.37904/metal.2020.3512
Z. Kuboň
{"title":"SMALL PUNCH TESTING OF THICK WALLED PIPE MADE OF THE STEEL P92 WITH HETEROGENEOUS MICROSTRUCTURE","authors":"Z. Kuboň","doi":"10.37904/metal.2020.3512","DOIUrl":"https://doi.org/10.37904/metal.2020.3512","url":null,"abstract":"The paper deals with the small punch testing of material properties including short-term creep resistance and microstructure analysis a thick-walled pipe made of P92 steel, where metallographic analysis revealed numerous internal defects, especially close to the inner surface of the pipe. These defects had their origin in the shrinkage porosity of the continuously cast slab and remained in the microstructure probably due to insufficient deformation during pipe rolling. The local material properties at the both inner and outer surfaces were compared by metallography, tensile tests, hardness tests, Charpy-V notch tests as well as small punch and small punch creep tests. The obtained results are compared with the material requirements for P92 steel and an attempt is made to evaluate the possible influence of the inhomogeneity of the microstructure and properties on the long-term service life of the pipe under creep conditions.","PeriodicalId":18449,"journal":{"name":"METAL 2020 Conference Proeedings","volume":"71 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74514430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
EXPERIMENTAL AND THEORETICAL DETERMINATION OF SPECIFIC HEATS, PHASE TRANSFORMATIONS TEMPERATURES AND ENTHALPY OF Fe-C-Cr-Ni ALLOWS 实验和理论确定比热，相变温度和焓的铁- c - cr - ni允许
METAL 2020 Conference Proeedings Pub Date : 2020-01-01 DOI: 10.37904/metal.2020.3530
S. Sorokina, B. Smetana, Ľ. Drozdová, M. Kawuloková, S. Zlá
{"title":"EXPERIMENTAL AND THEORETICAL DETERMINATION OF SPECIFIC HEATS, PHASE TRANSFORMATIONS TEMPERATURES AND ENTHALPY OF Fe-C-Cr-Ni ALLOWS","authors":"S. Sorokina, B. Smetana, Ľ. Drozdová, M. Kawuloková, S. Zlá","doi":"10.37904/metal.2020.3530","DOIUrl":"https://doi.org/10.37904/metal.2020.3530","url":null,"abstract":"Knowledge of thermodynamical and thermophysical properties of materials plays an important role for many industrial applications. The paper is dedicated to the study of three model alloys based on Fe-C-Cr-Ni. The studied alloys contained carbon in a range of 0.33 – 0.36 wt%, chromium 1.08 – 4.70 wt% and nickel 1.04 – 4.96 wt%. Thermophysical and thermodynamical properties depending on the composition of alloys such as specific heats, phase transformations temperatures and enthalpy were studied in low and high temperature areas. Experimental data were obtained using following devices: Setaram Sensys Evo and Setaram MHTC Line 96 with 3D DSC sensors. Specific heats were obtained using the continuous method. All measurements were performed in a helium atmosphere. The same properties were calculated using SW Thermo-Calc, then were compared and discussed with experimental data.","PeriodicalId":18449,"journal":{"name":"METAL 2020 Conference Proeedings","volume":"75 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74157303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Microstructure investigation and mechanical properties of Ti-6Al-2Sn-4Zr-6Mo alloy processed by hot rolling and solution treatment 热轧固溶处理Ti-6Al-2Sn-4Zr-6Mo合金组织与力学性能研究
METAL 2020 Conference Proeedings Pub Date : 2020-01-01 DOI: 10.37904/metal.2020.3580
M. H. Alluaibi, Saleh Sabah Alturaihi, D. Raducanu, Adrian Rusea, I. Cincă, A. Nocivin, V. Cojocaru
{"title":"Microstructure investigation and mechanical properties of Ti-6Al-2Sn-4Zr-6Mo alloy processed by hot rolling and solution treatment","authors":"M. H. Alluaibi, Saleh Sabah Alturaihi, D. Raducanu, Adrian Rusea, I. Cincă, A. Nocivin, V. Cojocaru","doi":"10.37904/metal.2020.3580","DOIUrl":"https://doi.org/10.37904/metal.2020.3580","url":null,"abstract":"The Ti-6Al-2Sn-4Zr-6Mo (Ti-6246) titanium alloy is categorized as one of α + β titanium alloys group, which plays an important role in the aerospace applications. This study aims to find out the optimal thermomechanical processing route to obtain a good balance of strength, ductility and fracture toughness. The Ti-6246 alloy was hot-deformed at a temperature of 900°C, with a total deformation degree of approximately 60%, and heattreated by a solution treating at temperatures between 800°C 1000°C for 18 minutes. The microstructural evolution, mechanical properties and fractography analysis were investigated. Results revealed that the volume fraction of the primary α (αp) phase decreases progressively until it is completely dissolved with increasing solution temperature; the secondary α (αs) phase increases whereas its width decrease with increasing solution temperature, and also the yield stress and ultimate tensile strength decrease with increasing solution temperature. A good balance of ultimate tensile strength and ductility was obtained in the case of a solution temperature of 900°C, which showed a tensile strength close to 812±4 MPa and an elongation close to 11.1±2.4 %. The fine αs phase facilitates the paths of crack propagation, meaning decrease the crack propagation resistance and decrease the ductility and fracture toughness.","PeriodicalId":18449,"journal":{"name":"METAL 2020 Conference Proeedings","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75096957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Laser remelting of Ni-Cr-Re plasma spraying coating Ni-Cr-Re等离子喷涂涂层的激光重熔
METAL 2020 Conference Proeedings Pub Date : 2020-01-01 DOI: 10.37904/metal.2020.3562
M. Węglowski, J. Dworak, S. Dymek, I. Kalemba-Rec, A. Wrona, K. Kustra, M. Lis
{"title":"Laser remelting of Ni-Cr-Re plasma spraying coating","authors":"M. Węglowski, J. Dworak, S. Dymek, I. Kalemba-Rec, A. Wrona, K. Kustra, M. Lis","doi":"10.37904/metal.2020.3562","DOIUrl":"https://doi.org/10.37904/metal.2020.3562","url":null,"abstract":"The plasma spray technology allows spraying a wide variety of materials. Atmospheric plasma spraying (APS) consists in injecting a powder feedstock material in a plasma jet to melt and accelerate the injected particles and spray them onto a substrate. The coating growth is thus realized by the impingement and spreading of sprayed particles. This mechanism of coating formation induces the presence of pores and micro-cracks. In order to eliminate those drawbacks, laser remleting may be used to improve the properties and performances of plasma sprayed coatings. In the present paper, the Ni20%C + 20%Re coating fabricated by plasma spraying on stainless steel substrate were remelted by CO 2 laser, and the effect of laser remelting on microstructure and hardness of plasma sprayed Ni20%Cr + 20%Re coating were studied. The microstructure of plasma sprayed and laser remelted coatings were analyzed using scanning election microscopy (SEM) and energy disperse spectroscopy (EDS). The micro-hardness of coating was measured using micro-hardness tester. The results show that the laser remelted coating becomes much denser moreover, the chemical composition of the coatings becomes homogeneous","PeriodicalId":18449,"journal":{"name":"METAL 2020 Conference Proeedings","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75849340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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