摘要
采用冷压法、热压法和挤压法3种方式制备了预制体试样,研究试样在不同加热炉温下的发泡行为。结果表明:采用冷压法时,几种加热温度下制备的预制体均不能发泡;采用热压法制备的预制体的发泡效果随加热速度而异,炉温为725℃时,没有发泡,试样裂开;炉温为750℃和800℃时,试样发泡成功;采用挤压法制备的预制体在不同炉温下均能发泡。当压力平衡温度(Tp)小于可发泡温度(Tf)时,预制体不能发泡;当Tp>Tf时,预制体可以发泡,且△(Tp-Tf)越大,发泡效果越好;预制体制备方式和加热速度对PCM法制备泡沫铝的发泡效果和行为有显著影响,其中采用挤压法制备的预制体性能最好。
The foaming behavior of Al-TiH2 precursor made by different compaction methods of cold pressing, hot pressing and extrusion at different furnace temperatures was studied. The results show that the precursor made by cold pressing cannot foam no matter what the furnace temperature is. The foaming behavior of precursor produced by hot pressing changes with heating rate, the precursor cannot foam and crack occurs at furnace temperature of 725℃, inversely, it can foam at furnace temperature of 750℃ and 800℃. The precursor made by extrusion can foam at any furnace temperature under the experimental condition. Based on theory analysis of experiment results, pressure balance temperature （Tp） and foaming temperature （Tf） were defined. Foaming mechanism and influence of precursor compaction methods and heating rate on foaming behavior were explored using the concepts of Tp and Tf. It is clarified that precursor processing methods and heating rate have remarkable effects on foaming behavior of PCM aluminum foams and the extrusion method is the best one for preparation of PCM aluminum foams.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2007年第7期1135-1142,共8页
The Chinese Journal of Nonferrous Metals
基金
山西省留学归国人员科技基金(200540)
关键词
泡沫铝
PCM法
前驱体
发泡行为
aluminum foam
PCM method
precursor
foaming behavior
