【摘 要】
:
The effects of silicon particle content and testing temperature on friction and wear properties of casting in-situ silicon particle reinforced ZA27 composites w
【机 构】
:
Key Laboratory of Gansu Advanced Nonferrous Materials
【基金项目】
:
the Doctor Foundation of Lanzhou University of Technology
论文部分内容阅读
The effects of silicon particle content and testing temperature on friction and wear properties of casting in-situ silicon particle reinforced ZA27 composites were investigated. The wear mechanisms were mainly discussed by observations of both worn surfaces and their side views. The results indicated that the variations of wear resistance with increasing of silicon particle content, at all of the testing temperatures applied, showed a similar tendency with a manner of non-monotonous change. It was surpdsed that the wear resistance decreased with the increase of silicon particle content from 2 vol.% to 5 vol.%, while it increased when the content was less than 2 vol.% or more than 5 vol.%. Similarly, the friction coefficient also did not change monotonously. The dominative wear mechanism changed from a relatively severe regime of plastic deformation accompanied by adhesion wear to a mild regime of smear, then to a very severe regime of severe plastic deformation induced wear, and finally again to a relatively mild regime of smear accompanied by abrasive wear as the silicon content increased. The wear resistance always decreased with elevating testing temperature, but the decrease ranges were different for the composites with different silicon contents. The friction coefficients changed irregularly for the different composites with the increase of testing temperature. Correspondingly, the wear mechanism alternated from a mild regime of smear accompanied by abrasive wear to a severe regime of plastic deformation accompanied by adhesion wear.
其他文献
随着农村畜牧业产值比重的大幅提高,农村畜牧兽医队伍对畜禽生产的重要性越来越突出,但目前农村畜牧生产、疫病防控等方面还存在诸多困难,严重制约着畜牧生产力的充分发挥,主要问
This paper proposed a cross-layer dual adaptive coded modulation architecture using turbo codes for mobile multimedia communication, which simultaneously adapte
高中时期的物理教学对于学生的学习水平有着重要的提升作用,能够帮助学生建立起良好的学习习惯和学习信心。目前的传统教学方式陷入了僵化的固定思维当中,无法适应当前的教育
This article studies the degree distribution property of low density parity check (LDPC) codes by Gaussian approximation (GA) and presents an efficient hybrid a
Todays firewalls and security gateways are required to not only block unauthorized accesses by authenticating packet headers,but also inspect flow payloads agai
A method was presented to implement the detecting and tracking of moving targets through omnidirectional vision.The method combined optical flow with particle f
A novel mobile self-reconfigurable robot is presented. This robot consists of several independent units. Each unit is composed of modular components including u
To enable quality scalability and further improve the reconstructed video quality in rate shaping, a rate-distortion optimized packet dropping scheme for H 264
当今,城市群正成为中国城市化进程的主体。笔者选择长三角、京津冀和殊三角三大城市群作为经验研究案例,以城市群经济空间的宏观形态为研究视角,选择GDP、非农人口、工业产值、固定资产投资与外商直接投资5大指标,采用空间趋势面方法,借助Surfer8.0软件进行了1995、2001与2005年的三维图谱信息历时性分析研究。最后,归纳提炼出三大城市群的能级主导均衡路径特征分别为:长三角城市群为"单极-扇面"
Resistance spot welding(RSW) is an efficient and convenient joining process for aluminum alloy sheet assembly. Because the RSW has the character of energy conce