Vacuum Sintering Furnace
The vacuum sintering furnace is the core heat treatment equipment for NdFeB permanent magnet production. Magnet green bodies after orientation compaction are loaded into the furnace chamber. Under a high-vacuum sealed environment, sintering and densification are completed through staged heating, holding and cooling following the preset process curve.
At high temperature, solid-phase diffusion takes place among magnetic powder particles and pores shrink and close. The loose green bodies shrink and densify into high-strength metallic magnets. Meanwhile, the internal grain size is precisely controlled, which directly determines key magnetic properties including remanence, coercivity and maximum energy product.
The vacuum atmosphere effectively prevents oxidative burning loss of rare earth elements at high temperature and reduces defect rates such as cracking, deformation and voids. It ensures stable performance consistency across batches. It is an indispensable key process equipment between compaction green body forming and mechanical precision machining.