铝质黏结剂型壳材料与制备工艺研究

Study of Aluminium Binder Shell Materials and Preparation Technology

在高温合金熔模精密铸造中,黏结剂的选择是一项最为关键的核心技术。常用的传统黏结剂为硅质黏结剂,然而这种黏结剂在高温下会化学分解,进而引起强度损失,限制了它的发展。铝质黏结剂具有熔点高、结构稳定的特点。本文通过对比铝质黏结剂型壳材料在不同条件下的工艺参数,初步确定了铝溶胶在精密铸造应用方面的技术指标及其匹配性。通过在铝溶胶涂料中加入质量分数为0.4%Cr+(III)离子溶液,初步解决了铝溶胶水溶可逆的问题,并研究了一种铝溶胶-硅溶胶复合壳型,其在1500℃时有8.4 MPa的高温抗弯强度。

In superalloy investment casting,the choice of binder is the most critical core technology.The commonly used traditional binder is a siliceous adhesive.However,this binder chemically decomposes at high temperatures,causing strength loss,thus limiting its development.The aluminium binder has the characteristics of a high melting point and stable structure.By comparing the process parameters of aluminium binder shell materials under different conditions,the technical indicators of aluminium sol in precision casting applications as well as the matching of various technical indicators have been preliminarily determined.By adding a 0.4 wt.%Cr+(III)ion solution to an aluminium sol coating,the problem of the reversible water solubility of the aluminium sol is initially solved.Finally,an aluminium sol-silica sol composite shell with a high-temperature bending strength of 8.4 MPa at 1500℃was studied.