發(fā)布時間：2017-12-27 06:15

  本文關鍵詞：激光熔蝕內部孔穴形態(tài)及相態(tài)變化　出處：《化工學報》2017年S1期 　論文類型：期刊論文

  更多相關文章： 脈沖激光 內部空穴 相變 分子模擬 微尺度

【摘要】：采用分子動力學方法對皮秒脈沖激光在晶體材料內部熔蝕出空穴的過程進行了模擬研究。通過記錄整個燒蝕過程中粒子速度和位置的變化得到了材料形態(tài)變化的原子圖像;同時,對粒子動能和受力進行統(tǒng)計分析得到了整個材料內部的應力傳導和溫度變化分布,并利用P-T相圖對特定位置處的材料相態(tài)變化進行了分析。結果表明:僅處于特定能量密度范圍內的皮秒脈沖激光可在晶體材料內部加工出孔穴;激光能量在燒蝕點處的累積以及轉化會導致材料內部出現極強的應力波,并且應力的傳遞將導致燒蝕點處熔池中材料的噴濺與分離,并使材料內部產生結構缺陷;此外,在分析材料內部的溫度分布時可以發(fā)現激光燒蝕過程中的熱影響區(qū)極小,并且大部分在加熱過程中被破壞的晶格結構在材料冷卻后能得到恢復,但晶體材料中仍會存在分散的片狀晶格缺陷。
[Abstract]:A molecular dynamics method is used to simulate the cavitation process of a picosecond pulse laser in the crystal material. Recorded by changes in particle position and speed of the ablation process obtained atomic images of morphological changes of the material; at the same time, the particle kinetic energy and stress were analyzed by the entire material internal stress conduction and temperature distribution, and the use of P-T to the specific location of the phase diagram of phase change materials is analyzed. The results showed that: only in the picosecond pulse laser specific energy density range in crystal materials processed inside cavity; laser energy accumulated in the ablation point and the transformation will lead to internal stress of strong wave, transfer and stress will lead to expulsion and separation of the ablation point in the weld pool. And the material internal structure defects; in addition, in the analysis of the temperature distribution inside the material can be found in the heat affected zone of the laser ablation process is extremely small, and most of the lattice structure in the heating process can be recovered in the destruction of the material after cooling, but the crystal materials remain scattered lamellar lattice defects.
【作者單位】： 中國海洋大學工程學院;
【基金】：國家自然科學基金項目(51376164)~~
【分類號】：TN249
【正文快照】： 引言自1960年激光器問世以來,領域內眾多學者就對材料受激光點源輻照后產生的變化展開了大量的理論以及實驗研究[1-2]。激光加工因其非接觸性以及超精細加工能力被廣泛地應用于理論研究和工程實踐中,部分學者嘗試將激光應用于加工微槽道[3-5],這部分研究著重關注了材料被高能，

本文編號：1340574