摘要
研究了两相区双重退火工艺对β相区加工的TA15(ELI)(Extra Low Interstitial,低间隙元素含量)钛合金厚试样的断裂韧性和裂纹扩展速率的影响。结果表明,β相区加工、两相区双重退火的钛合金试样具有很高的断裂韧性和较低的裂纹扩展速率。这主要是由于在该加工和热处理工艺下获得了片层状组织。随着退火温度升高,α片层厚度的增加,疲劳裂纹扩展速率降低,断裂韧性升高。对疲劳裂纹扩展试样断口分析表明,在预裂区和疲劳裂纹稳态扩展区,裂纹以准解理方式扩展。
The thick TA15 （ELI, Extra Low Interstitial） titanium alloy plate was produced by β-processing and duplex annealing in （ α ＋ β） phase field. The crack propagation rate and the fracture toughness of the plate were performed. The experimental results show that lamellar microstructure and a good damage tolerance property of high fracture toughness and low fatigue crack propagation rate is obtained, under the condition of β-processing and annealing in （ α ＋ β） phase field. With the increase of anneal temperature in α ＋ β phase field, the thickness of α lamella increases while the fatigue crack propagation rate decreases and fracture toughness increases. SEM analysis on the fatigue crack propagation plan was performed, and the analysis results indicate that the fatigue crack propagates in the mode of quasi-cleavage fracture in the presplitting region and steady state growth region.
出处
《金属热处理》
EI
CAS
CSCD
北大核心
2007年第2期27-30,共4页
Heat Treatment of Metals
