(重慶大學(xué) 材料科學(xué)與工程學(xué)院, 重慶 400030)
摘 要: 采用徑向應(yīng)變控制法，在MTS880/810試驗(yàn)機(jī)上用d13mm×1.5mm的單相α-Ti合金管材，在(350±1)℃下進(jìn)行了5個(gè)不同應(yīng)變量的高溫低周疲勞(HTLCF)實(shí)驗(yàn)； 記錄了各自的循環(huán)應(yīng)力—應(yīng)變滯后環(huán)， 得出了試樣的循環(huán)響應(yīng)特征和各試樣的高溫低周疲勞壽命。對實(shí)驗(yàn)數(shù)據(jù)按Coffin-Manson公式擬合出疲勞曲線方程，從而繪出了該試材的Δεt—2Nf倍壽命關(guān)系曲線。考慮到低周疲勞數(shù)據(jù)的離散性， 對其中的Δεt=1.0%和Δεt=1.5%兩個(gè)應(yīng)變量的各6個(gè)試驗(yàn)數(shù)據(jù)按雙參數(shù)Weibull分布進(jìn)行了統(tǒng)計(jì)分析。
關(guān)鍵字: 鈦合金；管材； 高溫低周疲勞
temperature low cycle fatigue
（College of Material Science and Engineering,
Chongqing University, Chongqing 400030）
Abstract:The high temperature low cycle fatigue (HTLCF) of d13mm×1.5mm single phase α-Ti alloy pipe materials was tested with five different strain parameters at (350±1)℃ on the test equipment of MTS 880/810, by the method of radial strain control. The individual cycle—strain hysteresis loops were recorded, and the cycling response and high temperature low cycle fatigue life were obtained.The experimental data were treated as fatigue curve formula according to Coffin-Manson formula, then the fatigue life curve Δεt—2Nf of tested materials was drawn. In consideration of the scatter of low cycle fatigue data, statistical analysis was applied to the six experimental data of two strain parameters Δεt=1.0% and Δεt=1.5% based on dual parameters Weibull distribution.
Key words: titanium alloy; pipe specimens; high temperature low cycle f
