摘要
以NH_4HCO_3为造孔剂,利用元素粉末混合烧结法制备了多孔NiTi形状记忆合金。研究了压制压力、烧结温度和烧结时间对多孔NiTi合金孔结构的影响,并分析了其物相组成。结果表明:随压制压力的增加,平均孔径和孔隙率逐渐减小;随烧结温度提高,多孔NiTi合金的平均孔径减小、孔隙率先增加后减少,孔隙分布趋于均匀;随烧结时间延长,多孔NiTi合金的平均孔径及孔隙率先增加后减少。在造孔剂添加量50%,压制压力250 MPa,烧结温度1000℃,烧结时间6 h条件下可制备出孔结构均匀(平均孔径为314μm,孔隙率56.3%)的多孔NiTi合金,其基体相为B2(NiTi)相。
Porous NiTi shape memory alloys（NiTi SMA） were fabricated by elemental powder complex sintering method using NHaHCO3 as pore-forming agent. The effects of pressing pressure, sintering temperature and sintering time on the pore structure of the prepared porous NiTi SMA were studied, and the phase composition was analyzed. The results show that： with the increase of pressing pressure, the average pore size and porosity gradually decreases; with the increase of sintering temperature, the average pore size gradually decreases and the porosity increases firstly and then decreases, and the pore distribution tends to be uniform; with the sintering time extending, both the average pore size and the porosity increases firstly and then decreases. With the process that adding 50% pore-forming agent, forming under the pressure of 250 MPa, and sintering at 1000℃ for 6 h, the porous NiTi alloy with homogeneous pore structure （average pore size of 314μm and the porosity of 56.3%） can be obtained, then, the phase composition of matrix is mainly B2 （NiTi）.
出处
《热加工工艺》
CSCD
北大核心
2016年第8期58-62,共5页
Hot Working Technology
基金
金川集团校企预研基金项目(201103)
