TiC颗粒增强钛基复合材料的热变形行为研究  

Study on Hot Deformation Behavior of TiC Particle-Reinforced Ti Matrix Composites

作　　者：奚正平[1,2] 王蕊宁 赵永庆[1] 戚运莲[1] 

机构地区：[1]西北有色金属研究院,陕西西安710016 [2]西部金属材料股份有限公司,陕西西安710065

出　　处：《稀有金属材料与工程》2009年第8期1338-1342,共5页Rare Metal Materials and Engineering

基　　金：国家重点自然科学基金(50434030);国家"973"项目(2007CB613807)

摘　　要：在Gleeble-1500热模拟试验机上进行热压缩试验，研究了变形温度为900～1150℃，应变速率为0．001～10s^-1的TiC颗粒增强钛基复合材料的热变形行为。根据所得应力应变曲线分析了该合金的热变形特征，计算了α＋β区域的平均变形激活能为799kJ／mol，口区域平均变形激活能为105kJ／mol。并根据动力学模型建立了加工图，分析了加工图中的高功率耗散区和流变失稳区，确定了不同区域的变形机制。观察了变形后的显微组织。结果表明：在温度范围为900～980℃，应变速率范围为O．001～0．1s^-1的低应变速率区域发生了超塑性和动态再结晶；在温度范围为1000～1100℃；应变速率范围为0．1～10s^-1的高应变速率区域变形机制主要是由亚晶界迁移扩散控制的动态再结晶。两个流变失稳区分别发生在温度为900～950℃，应变速率为0．1～10s^-1的区域和温度为1080～1130℃，应变速率为0．001～0．01s^-1区域。The hot deformation behaviors of TiC particle-reinforced Ti matrix composites were studied at the temperature range of 900-1150 and the strain rate range of 0.001-10s^-1 on the Gleeble-1500 simulator by the hot compression test. On the basis of the obtained stress-strain curves, the hot deformation characteristics of the alloys were analyzed; the average deformation activation energy of 799 kJ/mol in the （α＋β） region and 105 kJ/mol in the β region were calculated using kinetic rate equation, and the processing map for hot working was established based on the kinetic model The high-power dissipation region and flow instability region in the processing map were analyzed. The deformation mechanism of different regions in the processing map was determined and the microstructure evolution after deformation was observed and studied. The results show that superplastic deformation and dynamic recrystallization was observed at 900-980 ℃ and 0.001-0.1 s^-1; the leading deformation mechanism is dynamic recrystallization which controlled by sub-boundary migration and diffusion at 1000-1100 ℃ and 0.1-10 s^-1; and the two flow instability regions appeared at the temperature range of 900-950 ℃ and strain rate range of 0.1-10 s^-1 and the temperature range of 1080-1130 ℃ and strain rate range of 0.001-0.01s^-1 according to the processing map.

关 键 词：TIC颗粒增强钛基复合材料 热变形 加工图 变形机制 

分 类 号：TB33[一般工业技术—材料科学与工程]