With the development of investment casting technology of casting equipment, the types of mold materials are becoming more and more varied, and the compositions are different. Usually, according to the melting point of mold material, it is divided into high temperature, medium temperature and low temperature mold material. The description is as follows:

1. The melting point of low-temperature mold is lower than 60°C. Currently, 50% of paraffin-stearic acid mold, which is widely used in China, belongs to this category.

The melting point of high-temperature mould material is higher than 120°C, and the mould material composed of 50% rosin, 20% floor wax and 30% polystyrene is a typical high-temperature mould material.

The melting point of medium temperature mould material is between the two types of mould material mentioned above. The medium temperature mould material can be divided into rosin base and wax base mould material.

2. Basic requirements of mold properties

Thermophysical properties: suitable melting temperature and solidification interval, small thermal expansion and contraction, high heat resistance (softening point) and mold material should have no precipitant in liquid state and no phase transition in solid state.

Mechanical properties: strength, hardness, plasticity, flexibility and so on.

Process performance: mainly has the viscosity (or the fluidity), the ash content, the coating ability and so on.