According to the differences of type and time from setting to heating,investments were designed for such 6 groups as CBP,CBPF-30,CBPF-60,CQ-20,CQ-40 and CQ-60.The setting expansion and thermal expansion of each group were measured.

• 根据包埋料类型及包埋后放置时间不同分组为CBP、CBPF-30、CBPF-60、CQ-20、CQ-40、CQ-60。