材料期刊网

PHSICAL MODELLING AND PROCESSING OF Ti-6Al-4V ELI

C.P. Chou , S.C. Wang , C.C. Chang and W.R. Wang 1) Department of Mechanical Engineering , National Chiao Tung University Hsinchu , Taiwan 300 , China 2) Materials Research Laboratories , Industrial Technology Research Institute Chutung , Taiwan 310 , China

金属学报(英文版)

Titanium has been widely used as the implant materials of joint prostheses. This paper simulates the microstructures of the hot forged titanium knee joint component by physical modeling. Ti-6Al-4V ELI were deformed by GLEEBLE 2000 hot deforma- tion simulator in compression mode to determine the hot workability, in the range of 900 to 1100℃, with the strain rates between 0.05 to 5 s~(-1). Test results derived from specimens processed by on-cooling test and on-heating test were compared, thereby estimating the effect due to thermal history. The forging process of Ti-6Al-4V ELI tibial base plate of knee joint prostheses was design based on the workability data obtained.

关键词: physical modeling , null , null , null , null

Novel hard materials with controlled (W_0.5Al_0.5)C grain shapes: in-situ high pressure preparation and mechanical properties

Zhuhui QIAO

金属学报(英文版)

A novel hard material with various (W_0.5Al_0.5)C grain shapes was successfully prepared through mechanical alloying and in-situ high-pressure sintering process. X-ray diffraction apparatus and scanning electron microscopy were used to characterize the phase and the microstructures of the samples. The novel hard materials with ``fibrous", ``rounded" and ``plate-like" grains, which do not contain sharp edges, have the improved mechanical properties. The bulk boundless (W_0.5Al_0.5)C hard material with various (W_0.5Al_0.5)C grain shapes possesses good mechanical properties and light weight. The formation mechanism for the non-equilibrium (W_0.5Al_0.5)C grains during in-situ high-pressure sintering is also discussed.

关键词: Novel hard material

C700R-1耐热合金700℃时效组织和性能演变

田仲良 , 姜森宝 , 陈正宗 , 包汉生 , 刘正东

钢铁研究学报 doi:10.13228/j.boyuan.issn1001-0963.20160043

研究了新型汽轮机转子用C700R-1耐热合金700℃长期时效组织和性能的演变.研究表明：合金的主要析出相为 M23 C6、MC、γ′.C700R-1合金长期时效组织结构稳定,时效5000 h 晶界处 M23 C6碳化物平均宽度从190 nm增加至240 nm,呈不连续状态分布；时效5000 h球形γ′平均直径从22．0 nm粗化至49.8 nm,粗化速率缓慢.合金拉伸强度和硬度随时效时间延长先快速升高,后缓慢降低,并逐渐趋于稳定；理论计算 C700R-1合金中γ′临界尺寸为29.8 nm；长期时效后合金的冲击值在50 J 以上.

关键词: 汽轮机转子 , C700R-1 耐热合金 , 组织演变 , 性能演变

Isoplethic section in the quaternary system Fe-Co-Sm-Pr at 800 degrees C with Sm/Pr=1 and R <= 33.3 at% (R=Sm0.5Pr0.5)

Journal of Alloys and Compounds

Isoplethic section in the quaternary system Fe-Co-Sm-Pr at 800 degreesC with Sm/Pr=1 and R less than or equal to 33.3 at% (R=Sm0.5Pr0.5) was determined by using optical microscopy, X-ray diffraction analysis and electron probe microanalysis. There are five intermetallic phases: (Sm,Pr)(Fe,Co)(2), (Sm,Pr)(Fe,Co)(3), (Sm,Pr)(2)(Fe,Co)(7), (Sm,Pr)(5)(Fe,Co)(19) and (Sm,Pr)(2)(Fe,Co)(17). The isoplethic section of the Fe-Co-R system consists of eight single-phase regions, eleven two-phase regions and five three phase regions. The (Sm,Pr)(2)(Fe,Co)(7) phase in R-2(Fe1-xCox)(7) alloys dissolves nearly 15 at % Fe at 800 degreesC and no (Sm,Pr)(Fe,Co)(5) phase exists. (C) 2001 Elsevier Science B.V. All rights reserved.

关键词: transition metals;rare earth compounds;magnetically ordered materials;phase diagram;binary-system;magnetostriction

Mechanical alloying of Fe-Nb-C materials

Materials Letters

Mechanical alloying (MA) of elemental powder mixtures of Fe50Nb35C15, Fe60Nb30C10 and Fe50Nb40C10 was performed using a high energy ball mill. In the MA processing, ball milling first leads to a Fe-Nb-C amorphous phase and nanocrystalline NbC. Further milling results in the formation of a nanocrystalline solid solution of Fe(Nb, C) and nanocrystalline NbC in Fe50Nb35C15 and Fe60Nb30C10, while the final product for Fe50Nb40C10 is a mixture of amorphous Fe-Nb-C and nanocrystalline NbC.

关键词: mechanical alloying;Fe;Fe, Nb and C powders;amorphous;nanocrystalline;solid solution

MAGNETIC-PROPERTIES OF R2CO14(B,C) COMPOUNDS (R = Y, SM)

Journal of Applied Physics

The magnetic properties of R2Co14B1-xCx (x=0, 0.5 and R=Y, Sm) compounds have been studied by measuring the temperature dependence of the easy- and hard-magnetization curves on magnetically aligned samples between 1.5 and 300 K for Y2Co14(B,C) and at 4.2 K for Sm2Co14(B,C). The magnetic anisotropy of Y2Co14B increases due to the substitution of C for B, whereas the saturation magnetization decreases. Between 1.5 and 300 K, the anisotropy field of Y2Co14B0.5C0.5 increases about 2 T and the Co moment decreases about 0.05mu(B). The anisotropy field Of Sm2Co14B also increases upon C substitution and the saturation magnetization decreases slightly. The ac susceptibilities of both SM2Co14B and Sm2Co14B0.5C0.5 exhibit anomalies that may arise from a spin reorientation within the basal plane.

关键词: nd2fe14b;exchange;nd2co14b;r2fe14b;field

B4C(W,Ti)C陶瓷复合材料的制备及其性能

邓建新 , 周军

硅酸盐通报 doi:10.3969/j.issn.1001-1625.2002.01.004

采用热压烧结工艺制备了B4C/(W,Ti)C陶瓷复合材料.研究表明:B4C/(W,Ti)C陶瓷材料烧结时将产生化学反应,反应产物为TiB2和W2B5.B4C/(W,Ti)C陶瓷材料的性能与(W,Ti)C的含量密切相关,随(W,Ti)C含量的增加,材料的致密度、抗弯强度和断裂韧性逐渐增加,硬度逐渐减小;当保温时间低于50min时,材料的致密度、抗弯强度和硬度显著降低;B4C/(W,Ti)C陶瓷复合材料的最佳性能参数为:抗弯强度693MPa,维氏硬度23.5GPa,断裂韧性3.9MPa·m1/2.磨损实验表明,B4C/(W,Ti)C陶瓷材料在低速小载荷的实验条件下,耐磨性能优异,在高速大载荷的实验条件下,磨损过程中局部点的高温导致试样表面发生氧化,加剧了材料的磨损.

关键词: B4C , 陶瓷材料 , 复合材料

R410A和R407C饱和液相运动黏度测量

张颖 , 何茂刚 , 刘洋

工程热物理学报

改进了倾斜管式黏度测量实验系统,使其能够适用于非共沸物质饱和液相黏度的测量.对制冷剂 R22的替代物质一近共沸二元混合制冷剂R410A和非共沸三元混合制冷剂R407C的饱和液相运动黏度进行了测量,实验温度范围为256.15～336.15 K.同时,依据实验数据建立了制冷剂R410A和R407C饱和液相运动黏度与温度的关联式.

关键词: 运动黏度 , R410A , R407C , 实验测量

R407C地源热泵系统实验研究

李兴 , 俞坚

工程热物理学报

本文以三元非共沸混合工质R407C对传统工质HCFC22进行了替代,搭建了地源热泵系统实验台.考虑到在地源热泵运行时,地下土壤温度会因运行时间和冬夏季节的不同而发生变化,造成热泵的各种不同运行工况.为全面反映热泵的运行状态制订了测试方案,并对测试数据进行了整理和分析.该热泵系统在加热与制冷运行模式下COP均可达到3.6以上.

关键词: 地源热泵 , 混合工质R407C , 运行工况 , 性能测试

TEXTURES,INTERFACE AND FRACTURE OF A 1D-C/C PREPARED BY CVD

R.Shi , H.J. Li , Z. Yang and M.K. Kang(Dept. of Materials Science and Engineering , Northwestern Polytechnical University , Xi'an 710072 , China Manuscript received 26 August 1996)

金属学报(英文版)

A unidirectional carbon/carbon composite (1D-C/C) of low bulk density with textures of poruns granular and isotropic carbons sharply manifests brittle fracture and does not display high pseudoplasticity as expected. The results of transmisson electron microscopy (TEM) studies show that the strong interface of fiber-matrix should determine its fracture mode.

关键词: :1D-C/C , null , null , null