Metal Working and Material Science最新文献

{"title":"A systematic review of processing techniques for cellular metallic foam production","authors":"Shyam Sharma, Anurag Joshi, Y. Rajpoot","doi":"10.17212/1994-6309-2023-25.4-22-35","DOIUrl":"https://doi.org/10.17212/1994-6309-2023-25.4-22-35","url":null,"abstract":"Introduction. The paper presents a comprehensive overview of the manufacturing methods, materials, properties, and challenges associated with cellular metallic foams, primarily focusing on aluminum and titanium-based foams. Cellular metallic foams are gaining interest due to its unique combination of low density, high stiffness, and enhanced energy absorption capabilities. Cellular metallic foam is renowned for its special combinations of physical and mechanical characteristics, containing their increased stiffness, specific strength at high temperatures, light weight, and good energy absorption at relatively low plateau stress. It has extensive uses in the automotive, shipbuilding and space industries. It has high porosity, low relative density and high strength, which increases performance of the product. The aerospace and automotive industries require a material with a high strength-to-weight ratio. Methods. To meet this need, many metal foam production methods have been developed, such as melt route method, deposition method and powder metallurgy method. Melt route method is widely used to manufacture metallic foam as compared to other methods. Results and Discussion. In the production of aluminum foams, the melt route method is usually used. Titanium hydride (TiH2) has been a popular foaming agent, but its high decomposition rate and cost limitations have led to the development of alternative foaming agents, such as CaCO3 (calcium carbonate). Titanium foam is often manufactured using the space holder method. This method involves mixing titanium powder with a space holder material, forming a preform, and then sintering to remove the space holder and produce a porous structure as the space holder method allows for precise control over the properties of the foam, including pore size, porosity, and relative density. Results also indicate that porosity in cellular metallic foams can range from 50 % to 95 %, as reported in various journals. Pore structures can include mixed types, open cells, and closed cells, each offering different mechanical and thermal properties. It is also observed from various literature sources that relative density, which is the ratio of the foam's density to the bulk material's density, varies from 0.02 to 0.44 based on the production method used.","PeriodicalId":502919,"journal":{"name":"Metal Working and Material Science","volume":"85 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139183457","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}

{"title":"Modeling the interrelation of the cutting force with the cutting depth and the volumes of the metal being removed by single grains in flat grinding","authors":"Alexandra Akintseva, P. Pereverzev","doi":"10.17212/1994-6309-2023-25.4-6-21","DOIUrl":"https://doi.org/10.17212/1994-6309-2023-25.4-6-21","url":null,"abstract":"Introduction. The model for calculating the cutting force is the basis of the modules of CAM-systems related both to the predicting processing errors on metal-cutting machines for specified grinding conditions, and to the optimizing all parameters of the technological mode (parameters of cutting modes, cutting tools, etc.). However, due to the lack of an adequate model for calculating the cutting force presented in engineering form, such modules have not yet been developed not only for flat grinding operations, but also for all other types of metalworking. It is challenging to obtain an adequate cutting force model for flat grinding operations because it is necessary to establish the interrelation between the machine parameters of the macrocutting modes (feed, cutting speed) of the grinding wheel with the parameters of the microcutting modes — the sets of cutting grains of the wheel associated with the plastic deformation of the metal in the shear zone, microvolumes of the metal being removed and the geometry of the cutting part of the abrasive grains. The purpose of this work is to develop a force model establishing the interrelation of the cutting force with the cutting depth and the volumes of the metal being removed by single grains and the wheel as a whole on the basis of the integration of microvolumes and microforces when metal being removed by the wheel grains. Research methods. The subject of the research is the mathematical modeling of the interrelation between the cutting force and cutting modes with the parameters of microcutting by a group of single grains, based on the equality of work when metal being removed of the same volume. The methodological basis of the research is the connection between the work (energy) spent on the plastic deformation of metal by a single grain, the intensity of stresses, the intensity of deformation rates and the volume of the metal being removed by the wheel as a whole, established by S.N. Korchak. Results and discussion. The result of the study is an analytical model that reliably and adequately establishes the interrelation between the cutting force and the cutting depth, cutting modes, wheel characteristics, physical and mechanical properties of the processing material, and other main technological parameters. The field of application of the results is the possibility of using the cutting force calculation model, presented in this paper, as a basis for the development of a module for a CAM-system (a digital twin of the machining), which would allow to perform the calculation and design of optimal technological parameters of the flat grinding operation, as well as cutting modes testing according to the criterion of processing accuracy of a parts batch, considering the influence of various variable factors and real processing conditions within the manufacturing process.","PeriodicalId":502919,"journal":{"name":"Metal Working and Material Science","volume":"25 30","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139183957","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}

{"title":"Features of the formation of Ni-Cr coatings obtained by diffusion alloying from low-melting liquid metal solutions","authors":"E. Bobylyov, Ivan Storojenko, Anastas Matorin, Viacheslav Marchenko","doi":"10.17212/1994-6309-2023-25.4-232-243","DOIUrl":"https://doi.org/10.17212/1994-6309-2023-25.4-232-243","url":null,"abstract":"Introduction. The main ways to increase steel parts properties are considered. The rationale for choosing Ni and Cr as the main components of the coating is given. The technology of diffusion alloying from low-melting liquid metal solutions (DALMMS) is given. The purpose of this work is to identify the features of the coatings formation with simultaneous diffusion saturation of nickel and chromium structural steels using the DALMMS technology. Methodology. Cylindrical specimens with a diameter of 20 mm and a length of 30 mm were subjected to DALMMS. The specimens were manufactured of the following structural steels: carbon steel St3, alloyed carbon steels 40Cr, 40Cr13, and extrafine steel 30CrMnSiNi2. As a technological medium with DALLMS (transport melt), a Pb-Li eutectic melt with the specified content of Ni and Cr was used. Metallographic studies were carried out on microsections prepared according to the standard methodology. Studies to determine the thickness of coatings and its structure were carried out on the Dura Scan Falcon 500 microhardness tester. The elemental composition of the coatings was determined by the method of X-ray microanalysis on a Tescan Lyra 3 scanning electron microscope with the Oxford Ultim MAX PCMA system. Results and discuss. It is revealed that the formation of diffusive Ni-Cr coatings occurs with DALMMS. With DALMMS of structural steels contained carbon in cementite form two-layers coatings are formed: surface carbide layer and transition solid-soluble one. At the same time, the chromium content in the surface layers reaches 80 % with a nickel content of 1.5 %. The maximum Ni concentration is observed in the transition layer and amounts to 21 % at a depth of 5 µm on steel 30CrMnSiNi2 and 13 % at a depth of 4.5 µm for steel 40Cr. Carrying out the DALMMS on steels containing carbon in the form of chromium carbides, or containing carbon in small amounts, leads to the formation of single-layer coatings based on solid solutions. The Ni content in the coating reaches 40 %, the chromium content for steel St3 is 14.5 %; for steel 40Cr13 it was 9 %.","PeriodicalId":502919,"journal":{"name":"Metal Working and Material Science","volume":"466 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139183606","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}