摘要
利用应变诱发熔化激活法(SIMA)制备了7075铝合金半固态坯料。研究了半固态加热温度与保温时间对7075铝合金半固态坯料显微组织及压缩性能的影响。结果表明:半固态等温温度越高,球形率越好,液相率越高,初生α-Al固相颗粒的尺寸呈先降后升的趋势,而坯料的抗压强度则呈与之相反的趋势,等温温度595~610℃时达到理想状态;随着保温时间的延长,初生α-Al固相颗粒的球形率越好,颗粒尺寸逐渐增大,液相率无明显变化,而坯料的抗压强度呈先升高后略微下降的趋势,保温时间15~30 min时达到理想状态;在595℃保温30 min时,获得的7075铝合金半固态坯料的初生固相颗粒均匀、细小、圆整,抗压强度可达426.82 MPa。
The semi-solid billets of 7075 aluminum alloy were prepared by strain-induced melt activation technology （SIMA）. Effects of heating temperature and holding time on the microstructures and compression performances of the semi-solid billets of 7075 aluminum alloy were investigated. The results show that the higher semi-solid isothermal temperature is, the better the recrystallization nucleation rate is, the higher the rate of liquid phase is. The average grain size of primary o^-A1 solid particles has the tendency of first decreasing and then increasing, however, the compressive strength of semi-solid billets has the opposite trend, which achieves the ideal state at the isothermal temperature of 595~610 ~C. With the holding time prolonging, the spherical rate of primary o^-A1 solid particles is better, but the particle size is gradually increased and the liquid ratio is changed little. The compressive strength of semi-solid billets has the tendency of first increasing and then decreasing slightly, which achieves the ideal state at the holding time for 15-30 min. The optimized parameters are the defbnnation degree of 10%, the heating temperature of 595 ℃ and the holding time of 30 min. Under the above conditions, the semi-sold billets have the maximum compressive strength of 426.82 MPa.
出处
《铸造技术》
CAS
北大核心
2016年第4期701-705,共5页
Foundry Technology
基金
国家自然科学基金资助项目(51474091)
河北省自然科学基金资助项目(E2013209268)
河北省高等学校科学技术研究资助项目(Q2012011
Z2013129)
关键词
应变诱发熔化激活法
7075铝合金
半固态显微组织
抗压强度
strain-induced melt activation （SIMA）
7075 aluminum alloy
semi-solid microstructure
compressivestrength
