(西南交通大學(xué)機(jī)械工程學(xué)院，成都 610031)
摘 要: 采用改進(jìn)后的PLINT高溫可控氣氛的微動磨損試驗(yàn)機(jī)，研究Inconel 690合金在300 ℃氮?dú)饧胺ㄏ蚪蛔冚d荷條件下的微動磨損機(jī)制和動力學(xué)特性。結(jié)果表明: 微動運(yùn)行行為與激振頻率密切相關(guān)，微動的Ft-D曲線呈現(xiàn)摩擦力周期波動的平行四邊形型特征，微動運(yùn)行于滑移區(qū)。在300 ℃氮?dú)猸h(huán)境中，摩擦力的動態(tài)變化可以分為5個階段，即跑合階段、上升階段、峰值階段、下降階段和穩(wěn)定階段。Inconel 690合金的微動損傷行為強(qiáng)烈地依賴于載荷、位移幅值、環(huán)境溫度、氣氛及激振頻率等試驗(yàn)條件。從表面損傷形貌看，損傷微結(jié)構(gòu)與試驗(yàn)參數(shù)密切相關(guān)；由于交變法向力和切向力共同作用，微動產(chǎn)生疊加效應(yīng)，使剝層現(xiàn)象更加突出。在300 ℃氮?dú)猸h(huán)境下，Inconel 690合金的損傷機(jī)理主要表現(xiàn)為磨粒磨損和剝層。
關(guān)鍵字: Inconel 690合金；交變載荷；微動；高溫；疊加效應(yīng)；剝層
（School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, China）
Abstract:The frettingwear mechanisms and kinetic behaviours of Inconel690 alloy were investigated on the improved PLINT fretting rig under alternating loads conditions in high-temperature controlled-atmosphere environments. The results show that the fretting running behaviors are closely related to the normal excitation frequency. In parallelogram shaped Ft-D curves, the friction fluctuates periodically, and accordingly the fretting runs in the slip regime (SR). Five stages of friction force curves can be observedat 300 ℃in nitrogen environment, including initial stage, ascending stage, peak value stage descending stage and steady stage. The fretting wear behaviors for Inconel 690 alloy strongly depend on the normal load, displacement amplitude, temperature, atmosphere, excitation frequency and other test conditions. The super position effect of fretting wear behavior due to the combined effect of alternating normal force and tangential force is produced, so that delamination phenomenon becomes much more prominent. The abrasive wear and delamination are the major mechanisms of Inconel 690 at 300 ℃ in nitrogen environment.
Key words: alternating load; fretting wear; high temperature; superposition effect; delamination
