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在氢气或氢气和氩气混合的高压气氛中,采用定向凝固技术制备了规则多孔铜。定向凝固时晶体沿热流方向向上生长,凸向液相。由于气泡生长不会产生分叉,气泡稳态生长时,其生长只能以3种方式进行,即收缩生长气泡变小、平行生长气泡不变、膨胀生长气泡变大。比较三种生长方式的界面能,球冠夹角相同时,界面能由大到小依次为膨胀生长>收缩生长>平行生长。同时平行生长也能满足气泡在液-固界面前的力学平衡,说明中心上凸两侧平行向上的平行生长是符合的生长方式。试样中也证实了此生长方式的存在。
Regular porous copper was prepared by directional solidification in a high pressure atmosphere of hydrogen or hydrogen and argon. Directional solidification crystal growth along the direction of heat up, convex to the liquid phase. As the bubble growth does not produce bifurcation, the steady growth of the bubble, the growth can only be carried out in three ways, namely contraction of the growth of smaller bubbles, parallel growth of the same bubbles, expansion of growth bubbles. Compared with the growth of three kinds of interface energy, the same angle between the ball, the interface can descending order of expansion growth> shrinkage growth> parallel growth. At the same time, parallel growth can also satisfy the mechanical equilibrium of bubbles in front of the liquid-solid interface, indicating that parallel growth of both sides of the center convex upward is in line with the growth mode. Sample also confirmed the existence of this growth mode.