In-situ A1/24Si Functional Graded Materials Prepared by Electromagnetic Separation

Cylinder-like in-situ AI/24Si FGMs were produced by using electromagnetic separating process. Si primary phase reinforced layer with volume fraction as high as 16 pct was formed at the outer region of the cylinder-like samples where the local hardness and wear resistance were enhanced remarkably. Moreover, both of strength and ductility in the inner region provided insurance of reliable strength for this as-cast gradient material. It indicated that general mechanical properties such as good wear resistance at the outer region and good ductility in the central part could be obtained with the optimized redistribution of the Si primary particles under the electromagnetic force.

从考古发现看明末御器厂内的瓷器生产活动

一般认为,景德镇御器厂在万历以后停烧,一直到清初才再度恢复,期间大约有三四十年的生产空白。本文通过梳理古代文献和景德镇窑址的考古资料,初步得出以下两点认识:第一,明代御窑在天启、崇祯两朝完全停烧,但御器的供应未完全中断,而是沿袭前代的官搭民烧制度,御器继续且完全由民窑窑户来烧造供应,这种情况一直持续到清康熙十九年朝廷委派中央官员驻厂督陶、正式恢复御窑才停止;第二,在御窑停烧之后,原有场地和设备并未完全废弃,而是在一定程度上为民间窑户所利用,除烧造一些供御瓷器外,其余时间可以大量生产民用瓷器。由此,以往御器厂与民间窑场的生产隔离被完全打破了,二者之间的界限变得愈发模糊,这种情况一直到康熙时期才再次发生转变。