题目： 新型先进材料的研究与开发

报告人： Surojit Gupta博士

美国北达科他大学机械工程系助理教授

时间： 2014年8 月15日（星期五 ） 上午9时

地点： 材料学院1203，学术报告厅

（1）介绍先进制造研究中的一种新型测试方法，用来评价材料烧结过程中的应变、应力导致的尺寸改变以及重量改变。这种方法用来决定材料预烧结过程中的关键尺寸改变以及热-机响应。

（2）介绍先进陶瓷材料MAX相的摩擦学性能。最近发现MAX相陶瓷复合材料可以用于制造超级合金箔轴承的轴，可以在室温到550oC的温度范围内以每分钟5万转的速度工作。因为很少有材料可以在这个温度范围内做固体润滑材料，所以这种材料在箔片气体轴承、燃气轮机密封圈、低热柴油机密封圈等领域中重要的应用。

（3）介绍最近在新型环境友好结构材料方面的研究进展，这种材料不需要烧结，并且可以吸收空气中的二氧化碳，具有良好的力学性能。

本讲座是河南省双语教学示范课程《材料科学基础》的一部分。

报告人介绍：

Surojit Gupta, 2012.8-，美国北达科他大学机械工程系助理教授。https://engineering.und.edu/mechanical/faculty/surojit-gupta-info.cfm，2008.8-2012.7，美国罗格斯大学（Rutgers University）研究人员、Solida新材料公司技术顾问，主要研究吸收二氧化碳的环境友好结构材料。2006.8-2008.7，美国宾夕法尼亚州立大学博士后，研究蜂窝多孔陶瓷的制备过程。2001.9-2006.7，美国德雷塞尔大学(Drexel University)博士研究生，研究新型陶瓷材料MAX相的制备与摩擦学性能。

材料科学与工程学院

2014年7月10日

On the Development of Novel Advanced Materials

Surojit Gupta PhD

Department of Mechanical Engineering, University of North Dakota, Grand Forks, ND 58201

Abstract

In this presentation, I will present research findings on three different areas of materials research: (a) advanced manufacturing, (b) MAX phases (novel natural laminates) and their application in oil free engines, and (c) novel sustainable structural materials.

During Part A, a novel testing methodology for studying advanced manufacturing, which includes the evaluation of free sintering strain, stress-induced dimensional changes, and weight changes, will be presented. This methodology was developed to determine the critical dimensional changes and thermomechanical response during presintering (i.e., before densification).

During Part B, recent results on the tribological behavior of MAX phases will be presented. Mn+1AXn(MAX) phases (over 60+ phases) are thermodynamically stable nanolaminates displaying unusual, and sometimes unique, properties. These phases possess a Mn+1AXnchemistry, where n is 1, 2, or 3, M is an early transition metal element, A is an A-group element, and X is C or N. The MAX phases are highly damage tolerant, thermal shock resistant, readily machinable, and with Vickers hardness values of 2–8 GPa, are anomalously soft for transition metal carbides andnitrides.MAX phases display nonlinear, hysteretic, elastic behavior due to kink band formation in the basal planes.The Wd(energy dissipated per unit volume per cycle)of these crystalline solids are comparable to most woods. The composites of MAX phases with metals (MAXMET) are also important from both fundamental and applied perspective. Recently, it was demonstratedthat MAX Phase-based composites can be used as shafts against SA (Super Alloys) foils for different foil bearing applications at 50,000 rpm from RT till 550oC during thermal cycling. Earlier, despite several years of research there were no structural materials which could be used as a solid lubricant in the temperature range of RT to 550oC.Thus, there is a huge potential that these materials can be used for different tribological and engineering systems, for example, air-foil bearings, gas turbine seals, cylinder wall/piston ring lubrication for low-heat rejection diesel engines, various furnace components, among many others.

During Part C, recent studies about the development of novel sustainable materials will be presented.