固态物质在其形态为大尺寸时 ,熔点是固定的 ,超细微化后其熔点显著降低 ,当粒径小于 10ｎｍ时尤为突出。例如金的常规熔点为 10 64℃ ,当粒径减小到 10ｎｍ时 ,则降低 2 7℃ ,2ｎｍ时的熔点仅为 32 7℃左右。银的常规熔点为 970℃ ,而超微银颗粒的熔点可低于 10 0℃。因此 ,超 When the solid material has a large size, the melting point is fixed, and the melting point of the solid material is remarkably reduced when it is ultrafine, especially when the particle size is less than 10 nm. For example, gold has a typical melting point of 1064 ° C. When the particle size is reduced to 10 nm, it decreases by 27 ° C. The melting point at 2 nm is only about 32 ° C. The conventional silver melting point is 970 ° C, while the ultrafine silver particles may have a melting point below 10 ° C. Therefore, super