变形条件对QSn_(6.5-0.1)青铜流变应力及显微组织的影响

Deforming Conditions’ Effects on Bronze Flowing Stress and Microstructure of QSn_(6.5-0.1)

采用Gleeble-1500热模拟实验机,测定了QSn6.5-0.1青铜材料在热变形条件下的流变应力,分析了变形程度、变形速度、变形温度对流变应力及显微组织的影响规律.经回归分析,建立拟合精度较高的流变应力数学模型并建立起回归方程.通过扫描电子显微镜分析了合金在变形过程中的组织变化规律,随着变形温度的升高和应变速率的降低,亚晶尺寸增大,亚晶界处的位错排列更为简单和完整.合金变形时的软化机制主要为动态回复,动态再结晶只在较高温度和较低的应变速率情况下才出现.

The flowing stress curves of QSn6.5-0.1were determined at high temperature and high strain with a Gleeble-1500heat simulator.The effects of deforming temperatutes,deforming speed,deforming degree were analysed.By the analyses,a mathematical model with high fitting accuracy was proposed.By the analysis of microstructure with STM,the author found the size of subgrain increased and the dislocation substructure chang more completely and easily with the decrease of deforming temperature and strain rate.The alloy' restoration mechanism was mainly dynamic recovery while deforming,dynamic recovery was produced only under the conditions of high temperature and low strain rate.