金属粉末爆炸烧结中微碰撞焊接引起的沉能研究

Research of Energy Deposition Caused by Micro-Explosive Welding in Explosive Consolidation of Metal Powders

摘要:

以不可压缩理想流体对称碰撞模型对金属粉末爆炸烧结中由微爆炸焊接引起的颗粒界面附近沉积的能量进行了分析,在考虑热传导效应的基础上推导出了焊接流场中二维形式的能量方程并用有限差分法对其进行了求解,在考虑冲击绝热压缩贡献的基础上计算出了焊接流场中的温度分布.结果表明：在适当的冲击压力下,爆炸粉末烧结过程中微爆炸焊接引起的焊接界面附近的温升将达到材料的熔点而引起材料熔化,颗粒熔化部分仅为其表面很薄的一层;爆炸焊接引起的材料温升随来流速度和碰撞角度的增大而升高.

Abstract:

Energy deposition at the interface of the particles caused by micro-explosive welding in explosive consolidation of metal powders is analyzed by symmetrical impaction model of uncompressible liquid. Two-dimensional equation of energy in the flow field of explosive welding is deduced and solved by finite difference method. Then the distribution of the temperature in the flow field is calculated on the basis of considering the adiabatic compression. The results show that under an appropriate pressure the temperature rise near the welding interface caused by micro-explosive welding in explosive consolidation of metal powders will be higher than the melting point of the materials, and the thin melted layers are localized on the surfaces of the particles, the temperature rise increases with increasing of approaching flow velocity and impact angle.