(1. 中國(guó)科學(xué)院 金屬研究所，沈陽(yáng) 110016；
2. 東北大學(xué) 材料科學(xué)與工程學(xué)院，沈陽(yáng) 110819；
3. 中國(guó)科學(xué)院 福建物質(zhì)結(jié)構(gòu)研究所，福州 350002)
摘 要: 利用XRD、SEM、TEM和力學(xué)試驗(yàn)機(jī)等手段分析不同冷卻速率的TC16鈦合金試樣的相組成、顯微組織和力學(xué)性能，并分析冷卻速率對(duì)TC16鈦合金顯微組織和力學(xué)性能的影響。結(jié)果表明：TC16鈦合金經(jīng)800 ℃保溫處理后，水淬和空冷試樣均由α相、α″馬氏體、ω相和β相組成，爐冷試樣僅由α相和b相組成；水淬和空冷試樣中的初生α相體積分?jǐn)?shù)和晶粒尺寸都相近，均比爐冷試樣的小。水淬和空冷試樣的單向拉伸曲線(xiàn)上，出現(xiàn)雙屈服現(xiàn)象；隨著冷卻速率的降低，TC16鈦合金的屈服強(qiáng)度提高；水淬和空冷試樣的抗拉強(qiáng)度相近，高于爐冷試樣的；3種冷卻速度試樣的伸長(zhǎng)率和斷面收縮率相近，都具有優(yōu)異的室溫塑性。
關(guān)鍵字: TC16鈦合金；冷卻速率；顯微組織；力學(xué)性能；循環(huán)拉伸
（1. Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China;
2. School of Materials Science and Engineering, Northeastern University, Shenyang 110819, China;
3. Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China）
Abstract:The microstructure evolutions of the TC16 titanium alloy corresponding to different cooling rates at 800 ℃ were investigated by techniques of XRD, SEM and TEM. The tensile properties of each sample were finally evaluated. The results show that TC16 titanium alloy consists of primary a phase, α″ martensite, thermal w phase and metastable b phase in both water quenching and air cooling samples, but only primary α phase and metastable b phase are identified in furnace cooled sample. The volume fraction and grain size of primary α phase in both water quenching and air cooling samples are nearly the same, which are smaller than that of furnace cooling one. The dual yielding phenomenon was observed on the engineering stress-strain curves of both water quenching and air cooling samples. With decreasing the cooling rate, the yield strength of TC16 titanium alloy increases. The ultimate tensile strength of water quenching and air cooling samples exhibits the same value which is larger than that of furnace cooling one. Although the slight difference on the tensile strength for three kinds of samples, the elongation and area reduction representing the ductility are nearly the same.
Key words: TC16 titanium alloy; cooling rate; microstructure; mechanic property; cyclic tensile deformation
