Si-Zr-B涂层结构稳定性及对高温合金熔体的形核惰性

Structure Stability of Si-Zr-B Coating and Its Nucleation Inhibition Effect on Superalloy Melt

利用熔模制壳技术在壳型内壁制备了 Si- Zr- B基底涂层 (Si O2 79% ,Zr O2 1 8% ,B2 O3 3 % ,wt% )。再利用溶胶 -凝胶原理 ,在基底涂层表面制备了适宜厚度的同成分玻璃薄膜涂层。将涂层在1 5 0 0℃保温 3 0 min后 ,XRD结果表明 ,涂层的析晶量仅为 1 %～ 3 % ,具有很高的高温结构稳定性。过冷实验表明 ,DD3单晶高温合金可在该 Si- Zr- B涂层壳型内获得最大 1 40 K过冷度 ,完全可以实现深过冷快速凝固 ,证明 Si- Zr-

A Si-Zr-B glass coating was prepared with shell-molding technique, sol-gel processing and dipping class heat treatment procedure. It is found that B2O3 can inhibit crystallization of Si-Zr-B coating. The XRD patterns of Si-Zr-B coating show that the amount of crystalline at 1500%deg;C is only 1-3%, indicating that the coating is of high structure stability. The under cooling testing for DD3 single crystal superalloy melt with Si-Zr-B coating was performed at as much as 140 K. The SEM micrograph and XRD pattern of the contacting surface between the superalloy melt and the coating, and morphology of DD3 single crystal superalloy after rapid solidification show that Si-Zr-B coating makes the rapid solidification of the superalloy melt possible, which means Si-Zr-B has a good nucleation inhibition effect on DD3 single crystal superalloy melt.