| 摘要 |
PURPOSE:To obtain a single crystal of the titled alloy having a large amount of shape memory, causing no intergranular cracking, by providing a Cu-Zn-Al alloy material having shape memory with a given strain, passing it through a furnace in the atmosphere of air at a fixed speed. CONSTITUTION:A Cu-Zn-Al alloy having shape memory is melted, forged, rolled, so that the casting texture is destroyed. The alloy is annealed at about 700- 750 deg.C to remove the strain, to give a uniform alpha+beta texture free from internal strain. The alloy material is provided with about 1-3% strain again, and it is removed. The alloy material is drawn up from the low-temperature side to the high-temperature side through an electric furnace having a temperature gradient in the atmosphere of air so that it is heat-treated gradually. A crystal grain starts to grow with the rise in temperature, the phase of the crystal grain is changed into the phase of the crystal simultaneously with the enlargement of the crystal grain and it becomes a single beta grain shortly. The pulling is stopped at this stage, it is kept for about 30-60min as it is, the subgrain is removed, it is made into a solution, to give a single crystal material of alloy having shape memory. |
