电弧离子镀TiSiN薄膜的结构及摩擦性能

Microstructure and Friction Behavior of TiSiN Coatings Prepared by Arc Ion Plating

为实现电弧离子镀TiSiN薄膜成分可控,通过改变靶的相对电流在304不锈钢表面沉积TiSiN薄膜,采用厚度仪、能谱仪、扫描电镜、X射线衍射仪及摩擦试验研究了其形貌、结构及摩擦性能。结果表明:TiSiN薄膜中Si以非晶态Si3N4形式存在,抑制了面心立方结构的Ti N晶粒生长,形成纳米晶Ti N/非晶Si3N4(nc-Ti N/α-Si3N4)纳米复合结构;与Ti N薄膜相比,TiSiN薄膜具有更平整的表面,Si含量为4.08%(原子分数)时薄膜表面最光滑平整;Ti N薄膜的硬度为2 312 HK左右,掺杂Si元素后,由于细晶强化作用,薄膜的硬度显著提高,Si含量为2.76%(原子分数)时达到最大值,约为3 315 HK;进一步增加Si含量,TiSiN薄膜硬度略有下降;TiSiN薄膜的摩擦系数明显低于Ti N薄膜,且随着Si含量增加,摩擦系数逐渐变小,在Si含量为2.76%和4.08%(原子分数)时低至0.4左右。

TiSiN coatings were deposited on 304 stainless steel by arc ion plating while the current density of the target was adjusted for manipulating the composition of the coatings.The elemental composition,morphology and crystalline structure of as-prepared TiSiN coatings were analysed by energy dispersive spectrometry,scanning electron microscope and X-ray diffraction.A thickness gauge was performed to determine the thickness of the TiSiN coatings,and a friction and wear tester was performed to evaluate their friction behavior.Results indicated that Si in as-prepared TiSiN coatings existed in the form of amorphous Si_3N_4 thereby inhibiting the growth of face centered cubic TiN grains and affording nanocrystal TiN/amorphous Si_3N_4(denoted as ne-TiN/α-Si_3N_4) nanocomposite.As compared with TiN coating,TiSiN coating had more smooth surface,and the one containing 4.08%Si(atomic fraction;the same hereafter) possessed the maximum smoothness.Moreover,TiN coating had a hardness of about 2 312 HK,and TiSiN coating exhibited greatly increased hardness owing to refining effect associated with Sidoping.Particularly,the TiSiN coating with 2.76%Si had the maximum hardness of about 3 315 HK,and the hardness of the coatings tended to slightly decrease as the Si content rose above2.76%.Moreover,TiSiN coatings had friction coefficient much lower than that of TiN coating;the friction coefficient of the TiSiN coatings tended to gradually decline with increasing Si content,and their friction coefficient was reduced to about 0.4 as the Si content was in the range of 2.76%,4.08%.