摘要
含碳量为0.4a%的Ti-60合金在1135℃热处理水淬后析出形态规则的碳化物TiC.碳化物主要分布在β相晶粒内部,少量位于初生α(αp)相与β转变组织界面处和αp相内.合金随后在750-850℃时效处理后空冷,碳化物发生显著的溶解.β相晶粒内以及αp与β转变组织界面处β相晶粒一侧的碳化物,沿着β相方向优先溶解,造成碳化物形态不规则及其周围是贫β相的α基体.αp相晶粒内的碳化物以均匀、缓慢的速度溶解.从β相与碳化物的包析反应、位错和曲率作用等方面探讨了碳化物的溶解机制.
Dissolution behavior of carbide TiC in Ti-60 alloys with bimodal microstructure during ageing was investigated. Solution treatment in the （ α＋β ） phase field followed by quenching in water resulted in the precipitation of TiC carbide particles, most of which distributed in the β transformed grains and seldom at the interface of the primary α （αp） and β transformed grains or in the αp phase. The （α＋β） solution-treated specimens were aged in the temperature range of 750 to 850 ℃. For the carbide precipitate in the β transformed grain, the dissolution of carbide preferentially occurs from the β phase side, leading to the irregular shape of carbide particles and the β phase-poor matrix immediately surrounding the carbide. The carbide in the αp phase dissolves at an uniformly slow rate. The mechanisms of carbide dissolution are discussed in terms of the peritectoid transformation between the β phase and carbide, the movement of dislocations and the influence of curvature.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2005年第9期969-973,共5页
Acta Metallurgica Sinica
