摘要
铸态锡青铜组织中通常易形成Sn及P元素的偏析,造成合金的化学成分不均,从而增加合金脆性,影响合金的加工和使用性能。针对铸态ZCuSn10P1锡青铜开展退火工艺实验,以改善合金的成分不均现象。结果表明:退火处理对铸态ZCuSn10P1锡青铜中的Sn元素偏析改善有明显作用,但对于P元素偏析改善作用较小;随着退火时间的延长,合金中的树枝晶数量减少、晶粒粗化。在700℃退火2 h,铸态合金中的(α+δ+Cu_(3)P)三元共析组织得到有效分解,使晶间和基体中Sn元素分布的不均匀性得到明显改善;δ相随退火时间的延长逐渐减少,但很难完全消除。700℃退火2 h提升了铸态ZCuSn10P1锡青铜的塑性,冷轧至25%无开裂;经高温退火处理后因晶粒粗化,合金的布氏硬度有所降低。
Tin bronze has high strength and favorable wear resistance,it is used in bushings,bearings and other parts.The segregation of cast tin bronze is serious after cooling,and the segregation of Sn and P elements is easy to form in the as-cast tin bronze structure,resulting in uneven chemical composition of the alloy,thereby increasing the brittleness of the alloy and affecting the processing and performance of the alloy.In order to make the structure and composition more uniform,enhance the plastic deformation ability of the alloy,the annealing process was carried out on as-cast ZCuSn10P1 tin bronze to improve the phenomenon of uneven composition of the alloy in this paper.There were two sets of annealing process parameters,annealing at 700℃for 1~8 h and annealing at 400~750℃for 2 h.The microstructure and surface morphology were observed by optical microscope(OM),scanning electron microscope(SEM)and energy dispersive spectrometer(EDS),the phase was analyzed by X-ray diffractometer(XRD),and the electron probe analyzer(EPMA)was used for elemental quantitative analysis of samples with different annealing processes and as-cast conditions,and a Brinell hardness tester is used for Brinell hardness testing.The results showed that the black area in the as-cast alloy was the void defect left by the solidification of the casting.It could be seen from XRD pattern that the grain preferential orientation occurred in the local area,resulting in the inhomogeneity of the structure.Through EPMA analysis,it was found that the chemical composition was uneven due to the large amount of segregation of Sn,and(α+δ+Cu_(3)P)eutectoid structure.After annealing at 400~600℃ for 2 h,dendrites were still present,but Sn segregation area began to decrease,and the existence of voids was observed at 450 and 500℃,which indicated that the annealing treatment alone could not eliminate the residues left after solidification and casting.The defect existed in Cu41Sn11 phase in large quantities,which was due to the pores and small pores formed due
作者
肖寒
陈昊
崔鋆昕
周瑀杭
陈磊
张雄超
Xiao Han;Chen Hao;Cui Yunxin;Zhou Yuhang;Chen Lei;Zhang Xiongchao(Faculty of Materials Science and Engineering,Kunming University of Science and Technology,Kunming 650093,China)
出处
《稀有金属》
EI
CAS
CSCD
北大核心
2023年第6期815-824,共10页
Chinese Journal of Rare Metals
基金
国家自然科学基金项目(51965028)
云南省基础研究计划项目(202001AT070031)
昆明理工大学分析测试基金项目(2021T20100165)资助。
关键词
锡青铜
微观组织
退火工艺
力学性能
tin bronze
microstructure
annealing process
mechanical properties
