功能梯度类金刚石薄膜的脉冲激光制备

Fabrication of Functionally Gradient Diamondlike Carbon Films by Pulsed Laser Deposition

长期以来 ,高质量的纯类金刚石薄膜的成功制备一直受其巨大内部压应力的阻碍 ,因为这种压应力导致严重的附着问题。厚度大于 50 0nm的类金刚石薄膜中的压应力常使薄膜与基体剥离。作者采用功能梯度的设计概念 ,应用准分子脉冲激光沉积方法 ,成功制备了厚度超过 1 0 μm的高质量类金刚石薄膜。薄膜中的SP3碳原子含量超过 6 0 %。纳米硬度测试表明 ,薄膜的弹性模量高达 50 0GPa ,纳米硬度高达 6 0GPa ,薄膜与基体间附着良好。证明功能梯度的设计概念可以用于制备较厚的超硬类金刚石薄膜。

Fabrication of high quality diamondlike carbon(DLC)films has long been plagued by the large level of accumulated internal compressives stresses,which leads to serious adhesion concerns.Spallation has been observed when the film thickness exceeds 500nm.In this work,functionally gradient(FG)design was adopted to fabricate high quality thick DLC coatings via pulsed laser deposition,with the thickness exceeding 1 0μm.The fraction of SP\+3 carbons in the films was estimated to be more than 60%.Nanoindentation measurements indicated that the elastic modulus of the FG coatings is as high as 500GPa,and the nano\|hardness as high as 60GPa.The coatings adhere well to the substrate.It is proposed that the ideology of FG design may be applied for the fabrication of relatively thick superhard DLC coatings.