直管浇注法制备半固态坯料的研究

Preparation of Semi-solid Feedstock by Straight Pipe Pouring

采用直管浇注法制备出合格的铝合金半固态坯料,考察了尺寸不同的制备坩埚和直管在不同的温度状态下制备的坯料组织。结果表明,直管的冷却能力对坯料的组织有一定的影响。坯料的尺寸不同,直管的冷却能力对组织影响的程度也不一样,对较大坯料组织的影响要比较小坯料的大。对于80mm×150mm尺寸的坯料,直管在室温和通冷却水状态下都能获得比较理想的组织,但当直管温度达到200℃及以上温度时,坯料的组织不太理想;而对于98mm×150mm较大尺寸的坯料,虽然直管在室温和通冷却水状态下也都能制备出合格组织的坯料,但直管通冷却水后的坯料组织明显好于直管在室温时获得的组织。

Effects of crucible with different sizes and straight pipe on microstructure of semi-solid feedstock prepared by straight pipe pouring have been observed at different temperatures.It is found that the cooling capacity of straight pipe has some effects on microstructure of feedstock.In addition,the straight pipe has different effects on the feedstock with different size,in which the effects on microstructure of the billet with large size are higher.The desirable microstructure can be prepared by straight pipe pouring with cooling at room or water cooling for the feedstock with 80 mm in diameters and 150 mm in length,however,the microstructure is deteriorated with the pouring temperature more than 200 ℃.Although the feedstock with sound microstructure can be prepared by straight pipe pouring with cooling at room or water cooling for the billets with 98 mm in diameters and 150 mm in length,the microstructure of the semi-solid billets at water cooling is obviously superior to that of ones at room.