(西安交通大學 金屬材料強度國家重點實驗室， 西安 710049)
摘 要: 在往復沖擊載荷下對TiNiNb合金的沖擊磨損性能進行研究。 結果表明： 當單位面積沖擊能量為1.61 J/cm2時， TiNiNb合金表現(xiàn)出通常的耐磨行為， 磨損率始終維持穩(wěn)定； 但當單位面積沖擊能量上升到2.42 J/cm2且沖擊進行到30萬次后， 磨損率曲線發(fā)生轉折， 轉折后的磨損率僅為1.61 J/cm2沖擊時的1/2.1。 經(jīng)X射線衍射分析和掃描電鏡觀察發(fā)現(xiàn)， 磨損率下降的主要原因是高能沖擊30萬次后， 表層組織中出現(xiàn)大量的非晶， 導致通常的磨損機制在很大程度上受到抑制， 使磨損率急劇下降， 并因此使得高能量沖擊下的磨損量最終也低于低能量沖擊下的磨損量。
關鍵字: 沖擊磨損; TiNiNb形狀記憶合金; 非晶
（ State Key Laboratory for Mechanical Behavior of Materials,
Xi'an Jiaotong University, Xi'an 710049, China）
Abstract: The impact wear test to TiNiNb alloy was carried out, and an abnormal wear phenomenon was discovered. The TiNiNb alloy exhibits common wear behavior when the energy of per unit area is 1.6 J/cm2, and the wear rate keeps invariable all the time. When the energy of per unit area rises to 2.4 J/cm2 and the impacting times reach to 30×104, the wear rate curve shows a noticeable decrease, and the decreased wear rate is only 1/2.1 of that under 1.6 J/cm2. With the help of X-ray diffractrometry and transmission electron microscopy, it is found that after impacting with the energy of 2.4 J/cm2, a lot of amorphous appear in the surface layer of specimen after 30×104 times, the appearance of amorphous restrains strongly the common wear process so that the wear rate and wearing capacity are all lower than those under 1.6 J/cm2.
Key words: impact wear; TiNiNb alloy; amorphous
