Powder Metallurgy Progress最新文献_第6页

Phase Composition of Samarium Niobate and Tantalate Thin Films Prepared by Sol-Gel Method 溶胶-凝胶法制备铌酸钐和钽酸盐薄膜的相组成

Powder Metallurgy Progress Pub Date : 2017-12-01 DOI: 10.1515/pmp-2017-0002

H. Brunckova, Ľ. Medvecký, E. Múdra, A. Kovalčíková, J. Ďurišin, M. Sebek, V. Girman

{"title":"Phase Composition of Samarium Niobate and Tantalate Thin Films Prepared by Sol-Gel Method","authors":"H. Brunckova, Ľ. Medvecký, E. Múdra, A. Kovalčíková, J. Ďurišin, M. Sebek, V. Girman","doi":"10.1515/pmp-2017-0002","DOIUrl":"https://doi.org/10.1515/pmp-2017-0002","url":null,"abstract":"Abstract Samarium niobate SmNbO4 (SNO) and tantalate SmTaO4 (STO) thin films (~100 nm) were prepared by sol-gel/spin-coating process on alumina substrates with PZT interlayer and annealing at 1000°C. The precursors of films were synthesized using Nb or Ta tartrate complexes. The improvement of the crystallinity of monoclinic M′-SmTaO4 phase via heating was observed through the coexistence of small amounts of tetragonal T-SmTa7O19 phase in STO precursor at 1000°C. The XRD results of SNO and STO films confirmed monoclinic M-SmNbO4 and M′-SmTaO4 phases, respectively, with traces of orthorhombic O-SmNbO4 (in SNO). In STO film, the single monoclinic M′-SmTaO4 phase was revealed. The surface morphology and topography of thin films were investigated by SEM and AFM analysis. STO film was smoother with roughness 3.2 nm in comparison with SNO (6.3 nm). In the microstructure of SNO film, small spherical (~50 nm) and larger cuboidal particles (~100 nm) of the SmNbO4 phase were observed. In STO, compact clusters composed of fine spherical SmTaO4 particles (~20-50 nm) were found. Effect of samarium can contribute to the formation different polymorphs of these films for the application to environmental electrolytic thin film devices.","PeriodicalId":52175,"journal":{"name":"Powder Metallurgy Progress","volume":"17 1","pages":"10 - 20"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/pmp-2017-0002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42714527","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, Mechanical Properties and Corrosion Behaviour of Iron - Manganese PM Materials Pressed and Sintered Once and Twice 一次和两次烧结铁锰永磁材料的组织、力学性能和腐蚀行为

Powder Metallurgy Progress Pub Date : 2017-12-01 DOI: 10.1515/pmp-2017-0012

M. Kupková, M. Hrubovčáková, M. Kabátová, M. Kupka

引用次数: 0

The Effect of Powder Ball Milling on the Microstructure and Mechanical Properties of Sintered Fe-Cr-Mo-Mn-(Cu) Steel 粉末球磨对烧结Fe-Cr-Mo-Mn-（Cu）钢组织和力学性能的影响

Powder Metallurgy Progress Pub Date : 2017-12-01 DOI: 10.1515/pmp-2017-0009

P. Kulecki, E. Lichańska

引用次数: 6

Effect of Alloying Type and Lean Sintering Atmosphere on the Performance of PM Components 合金化类型和贫烧结气氛对PM元件性能的影响

Powder Metallurgy Progress Pub Date : 2017-12-01 DOI: 10.1515/pmp-2017-0008

M. V. Sundaram, R. Shvab, S. Millot, E. Hryha, L. Nyborg

{"title":"Effect of Alloying Type and Lean Sintering Atmosphere on the Performance of PM Components","authors":"M. V. Sundaram, R. Shvab, S. Millot, E. Hryha, L. Nyborg","doi":"10.1515/pmp-2017-0008","DOIUrl":"https://doi.org/10.1515/pmp-2017-0008","url":null,"abstract":"Abstract In order to be cost effective and to meet increasing performance demands, powder metallurgy steel components require continuous improvement in terms of materials and process development. This study demonstrates the feasibility of manufacturing structural components using two different alloys systems, i.e. lean Cr-prealloyed and diffusion bonded water atomised powders with different processing conditions. The components were sintered at two different temperatures, i.e. 1120 and 1250 °C for 30 minutes in three different atmospheres: vacuum, N2- 10%H2 atmosphere as well as lean N2-5%H2-0.5%CO-(0.1-0.4)%CH4 sintering atmosphere. Components after sintering were further processed by either low pressure carburizing, sinterhardening or case hardening. All trials were performed in the industrial furnaces to simulate the actual production of the components. Microstructure, fractography, apparent and micro hardness analyses were performed close to the surface and in the middle of the sample to characterize the degree of sintering (temperature and atmosphere) and the effect of heat treatment. In all cases, components possess mostly martensitic microstructure with a few bainitic regions. The fracture surface shows well developed sinter necks. Inter- and trans-granular ductile and cleavage fracture modes are dominant and their fraction is determined by the alloy and processing route.","PeriodicalId":52175,"journal":{"name":"Powder Metallurgy Progress","volume":"17 1","pages":"72 - 81"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48444664","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

Properties of Powder Composite Polyhydroxybutyrate–Chitosan-Calcium Phosphate System 粉末复合聚羟基丁酸酯-壳聚糖-磷酸钙体系的性能

Powder Metallurgy Progress Pub Date : 2017-12-01 DOI: 10.1515/pmp-2017-0001

Ľ. Medvecký, R. Stulajterova, M. Giretová, M. Fáberová

引用次数: 4

Density, Microstructure, Strength and Fractography of Spark Plasma and Conventionally Sintered Mn Steels 火花等离子体和常规烧结Mn钢的密度、组织、强度和断口形貌

Powder Metallurgy Progress Pub Date : 2017-12-01 DOI: 10.1515/pmp-2017-0010

M. Tenerowicz-Żaba, M. Kupková, M. Kabátová, E. Dudrová, M. Džupon, M. Sułowski

{"title":"Density, Microstructure, Strength and Fractography of Spark Plasma and Conventionally Sintered Mn Steels","authors":"M. Tenerowicz-Żaba, M. Kupková, M. Kabátová, E. Dudrová, M. Džupon, M. Sułowski","doi":"10.1515/pmp-2017-0010","DOIUrl":"https://doi.org/10.1515/pmp-2017-0010","url":null,"abstract":"Abstract The aim of the study was to investigate Spark Plasma Sintering (SPS) of 1-3%Mn steels and compare the resultant microstructures, strengths and failure mechanisms with those of conventionally sintered materials. SPS was performed in a vacuum of 5 Pa at 1000°C for 15min under a uniaxial pressure of 20 MPa. The heating rate of 100°C/min was applied. For conventional processing, mixtures of powders were prepared in a Turbula mixer for 30 minutes. Samples were single pressed at 660 MPa, according to PN-EN ISO 2740 standard. Sintering of compacts was carried out in a laboratory tube furnace at 1120°C and 1250°C for 60 minutes in a mixture of 95%N2-5%H2. Heating and cooling rates were 75C°/min and 60°C/min, respectively. The density of SPS samples was higher (up to 7.37 g/cm3) than those after conventional sintering (up to 6.7 g/cm3). Yield strengths of SPS samples were in the range 920-1220 MPa, compared to the maximum of 602 MPa for conventionally sintered Fe-3%Mn-0.8%C. Transverse rupture strengths were the same for this alloy, 1234 MPa, but reached 1473 MPa for SPS 2Mn variant. Interfaces in SPS samples were significantly less contaminated with oxides, which is the result of a more favorable microclimate and pressure acting during SPS. These preliminary results indicate that further research on the SPS of Mn steels is warranted.","PeriodicalId":52175,"journal":{"name":"Powder Metallurgy Progress","volume":"17 1","pages":"103 - 93"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43535941","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: 2

Plasticity Modelling in PM Steels PM钢的塑性建模

Powder Metallurgy Progress Pub Date : 2017-12-01 DOI: 10.1515/pmp-2017-0004

M. Andersson, V. Angelopoulos

引用次数: 0

The Effects of Post-Sintering Treatments on Microstructure and Mechanical Properties of Mn-Mo Steel 烧结后处理对Mn-Mo钢组织和力学性能的影响

Powder Metallurgy Progress Pub Date : 2017-12-01 DOI: 10.1515/pmp-2017-0011

C. Fiał

引用次数: 0

Embrittling Components in Sintered Steels: Comparison of Phosphorus and Boron 烧结钢的脆化成分:磷和硼的比较

Powder Metallurgy Progress Pub Date : 2017-12-01 DOI: 10.1515/pmp-2017-0006

H. Danninger, V. Vassileva, C. Gierl-Mayer

{"title":"Embrittling Components in Sintered Steels: Comparison of Phosphorus and Boron","authors":"H. Danninger, V. Vassileva, C. Gierl-Mayer","doi":"10.1515/pmp-2017-0006","DOIUrl":"https://doi.org/10.1515/pmp-2017-0006","url":null,"abstract":"Abstract In ferrous powder metallurgy, both boron and phosphorus have been known to be sintering activators for a long time. However, the use has been widely different: while P is a standard additive to sintered iron and steels, boron has been frequently studied, but its use in practice is very limited. Both additives are also known to be potentially embrittling, though in a different way. In the present study the differences between the effects of both elements are shown: while P activates sintering up to a certain threshold, in part by stabilizing ferrite, in part by forming a transient liquid phase, boron is the classical additive enhancing persistent liquid phase, being virtually insoluble in the iron matrix. The consequence is that sintered steels can tolerate quite a proportion of phosphorus, depending on composition and sintering process; boron however is strongly embrittling in particular in combination with carbon, which requires establishing a precisely defined content that enhances sintering but is not yet embrittling. The fracture mode of embrittled materials is also different: while with Fe-P the classical intergranular fracture is observed, with boron a much more rugged fracture surface appears, indicating some failure through the eutectic interparticle network but mostly transgranular cleavage. If carbon is added, in both cases transgranular cleavage dominates even in the severely embrittled specimens, indicating that no more the grain boundaries and sintering necks are the weakest links in the systems.","PeriodicalId":52175,"journal":{"name":"Powder Metallurgy Progress","volume":"17 1","pages":"47 - 64"},"PeriodicalIF":0.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46970242","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

Reaction of Unalloyed and Cr-Mo Alloyed Steels with Nitrogen from the Sintering Atmosphere 非合金钢和Cr-Mo合金钢与烧结气氛中氮气的反应

Powder Metallurgy Progress Pub Date : 2016-12-01 DOI: 10.1515/pmp-2016-0007

M. Dlapka, C. Gierl-Mayer, Raquel de Oro Calderon, H. Danninger, S. Bengtsson, E. Dudrová

{"title":"Reaction of Unalloyed and Cr-Mo Alloyed Steels with Nitrogen from the Sintering Atmosphere","authors":"M. Dlapka, C. Gierl-Mayer, Raquel de Oro Calderon, H. Danninger, S. Bengtsson, E. Dudrová","doi":"10.1515/pmp-2016-0007","DOIUrl":"https://doi.org/10.1515/pmp-2016-0007","url":null,"abstract":"Abstract Nitrogen is usually regarded as an inert sintering atmosphere for PM steels; however, this cannot be taken for granted in particular for steels alloyed with nitride forming elements. Among those elements, chromium has become more and more important as an alloying element in sintered low alloy structural steels in the last decade due to the moderate alloying cost and the excellent mechanical properties obtainable, in particular when sinter hardening is applied. The high affinity of Cr to oxygen and the possible ways to overcome related problems have been the subject of numerous studies, while the fact that chromium is also a fairly strong nitride forming element has largely been neglected at least for low alloy steel grades, although frequently used materials like steels from Cr and Cr-Mo prealloyed powders are commonly sintered in atmospheres consisting mainly of nitrogen. In the present study, nitrogen pickup during sintering at different temperatures and for varying times has been studied for Cr-Mo prealloyed steel grades as well as for unalloyed carbon steel. Also the effect of the cooling rate and its influence on the properties, of the microstructure and the composition have been investigated. It showed that the main nitrogen uptake occurs not during isothermal sintering but rather during cooling. It could be demonstrated that a critical temperature range exists within which the investigated CrM-based steel is particularly sensitive to nitrogen pickup.","PeriodicalId":52175,"journal":{"name":"Powder Metallurgy Progress","volume":"16 1","pages":"86 - 98"},"PeriodicalIF":0.0,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67337552","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: 2