摘要
Fatigue cracking behavior from a notch was investigated at room temperature for Ti-6.SAI-3.5Mo-1.5Zr- 0.3Si （TClI） alloys with four different microstructures obtained at different cooling rates from the β transus temperature. It was found that the alloy with lamellar structures consisting of α/β lamellae or acicular α＇ martensite laths had a higher fatigue crack initiation threshold from the notch, while the bimodal structure with coarse a grain had a lower fatigue cracking resistance. The alloy with α/β lamellar structure showed a higher fatigue crack growth resistance. The length scales of the microstructures were characterized to correlate with fatigue cracking behavior. Fatigue cracking mechanism related to microstructures was discussed.
Fatigue cracking behavior from a notch was investigated at room temperature for Ti-6.SAI-3.5Mo-1.5Zr- 0.3Si （TClI） alloys with four different microstructures obtained at different cooling rates from the β transus temperature. It was found that the alloy with lamellar structures consisting of α/β lamellae or acicular α＇ martensite laths had a higher fatigue crack initiation threshold from the notch, while the bimodal structure with coarse a grain had a lower fatigue cracking resistance. The alloy with α/β lamellar structure showed a higher fatigue crack growth resistance. The length scales of the microstructures were characterized to correlate with fatigue cracking behavior. Fatigue cracking mechanism related to microstructures was discussed.
基金
supported by the National Basic Research Program of China (No. 2007CB613803)
the National Natural Science Foundation of China (No.51071158)
the Fundamental Research Funds for the Central Universities (No. N100702001)
