摘要
为提高碳/碳复合材料抗高温氧化性,以粒度13μm左右的MoSi2粉末为原料,在乙醇溶液中于室温将MoSi2粉末电泳沉积在直径为30mm、厚度为5mm的碳/碳复合材料圆柱片表面,再经800℃氩气气氛烧结制得MoSi2涂层。电泳沉积的优化条件:电泳沉积电压95V,电极间距2cm,电泳沉积时间5 min。在此条件下制得的MoSi2涂层表面平坦、光滑,涂层质量为65.3mg,涂层平均厚度为46μm,涂层平均粘结强度为23.9 MPa。在优化电泳沉积条件下制得的MoSi2涂层可使碳/碳复合材料在1 500℃空气中静态氧化速率由原来的0.82%/min降至0.49%/min,80min内样品失重率由63%降为39%。在MoSi2涂层表面再涂覆一层Si-Al-O复合氧化物陶瓷涂层,可使样品氧化速率和样品失重率进一步分别减小为0.15%/min和11%。从对基材失重率的降低值贡献来说,双重涂层比单个涂层叠加效果要好,因此双重涂层对阻碍基材氧化可能有某种协同作用。
In order to improve the high temperature oxidation resistance of carbon/carbon composite material,the MoSi2 coating was prepared by electrophoretic deposition of MoSi2 powder with a particle size of about 13μm on the surface of carbon/carbon composite material cylinder with diameter of 30 mm and thickness of 5 mm in ethanol solution at room temperature,and then sintering in 800℃argon atmosphere.The optimal conditions for electrophoretic deposition are as follows：electrophoretic deposition voltage of 95 V,electrode gap of 2 cm and electrophoretic deposition time of 5 min.Under such conditions,the MoSi2 coating surface is flat and smooth with a weight of 65.3 mg,an average thickness of 46μm and an average binding strength of 23.9 MPa.The MoSi2 coating prepared under the optimal electrophoretic deposition conditions can reduce the static oxidation rate of carbon/carbon composite material in air at 1 500 ℃from 0.82%/min to 0.49%/min,and the weight loss rate of the sample decreases from 63%to 39% within 80 min.Applying a layer of Si-Al-O composite oxide ceramic coating on the surface of MoSi2 coating can further reduce the sample oxidation rate and weight loss rate to 0.15%/min and 11%,respectively.The dual coating is more effective than the addition of single coating in terms of reduction of substrate weight loss rate,so the dual coating may have some synergistic effects on inhibition of substrate oxidation.
出处
《稀有金属与硬质合金》
CAS
CSCD
北大核心
2018年第1期27-32,共6页
Rare Metals and Cemented Carbides
关键词
碳/碳复合材料
高温抗氧化涂层
MoSi2涂层
电泳沉积
涂层粘结强度
C/C composite material
high- temperature oxidation resistant coating
MoSi2 coating
electrophoretic deposition
hinding strength of coating
