超细硬质合金WC-6%Co-6%(W,Ti,Ta)C表面TiCN-Al_2O_3-TiN多层复合涂层性能分析

Microstructure and Properties of TiN-Al_2O_3-TiCN Multilayers on Ultra-fine Cemented Carbide WC-6%Co-6%(W,Ti,Ta)C

采用自主研发的超细硬质合金WC-6%Co-6%(W,Ti,Ta)C,利用化学涂层方法制备了TiCN-Al2O3-TiN多层复合涂层。利用X射线衍射仪、扫描电镜、自动划痕仪和显微硬度计对涂层进行了结构分析和性能检测。结果表明,整个涂层组织由3层组成,与基体结合层为TiCN,次外层为Al2O3,最外层为TiN,制得的Al2O3涂层主要为κ-Al2O3晶型,κ-Al2O3晶型有利于细化晶粒,多层复合涂层剥落的形式不仅使涂层和基体间会出现分离,涂层和涂层间也会出现分离,Al2O3涂层会降低涂层与基体之间的结合强度,涂层的平均结合力为69N,平均表面显微硬度为2 225HV。

TiCN-Al2O3-TiN multilayer coating is built by adapting self-developed cemented carbide WC-6% Co-6% （W, Ti,Ta）C and using chemical coating methods. The structure analysis and performance test of coating layer is examined by X-ray diffraction, scanning electron microscope, auto-scratch tester and microhardness tester. The result indicates that the whole coating layer is consisted of three layers. Bonding the substrate is TiCN, the middle layer is Al2O3 and outmost layer is TiN. Al2O3 coating is mainly composed of the crystal form of k-Al2O3which is good for the fined grain. The desquamate form multi-layer composite form will not only shown as coating and matrix separating, hut also the separating between coat- ing layers, meanwhile, the Al2O3 coating layer will decrease the bounding strength between coating and matrix. The average bonding force of Coating layer is 69 N and average surface hardness is 2 225 HV.