The difference between low-temperature wax and medium temperature wax in precision casting

The difference between low-temperature wax and medium temperature wax in precision casting

The term "low-temperature wax" and "medium temperature wax" in precision casting is an early term for mold materials. Although many people still use this term, strictly speaking, it should be referred to as "medium temperature mold material" or "low-temperature mold material". Today, precision casting manufacturer Tianyao Metal will talk to you about the differences between low-temperature wax and medium temperature wax in precision casting.

Due to the variety and composition of mold materials, their classification is also quite complex. There are two recognized classification methods:

1、 Divide based on the thermal stability of the mold material.

Thermal stability is an important performance of the mold material, which is closely related to its melting point. Generally speaking, the higher the melting point of the mold material, the higher its thermal stability; On the contrary, the lower the melting point, the lower its thermal stability. So, according to the melting point of the mold material, it can be divided into three categories: high melting point mold material, medium melting point mold material, and low melting point mold material. If considered from the perspective of thermal stability, it can be divided into high-temperature mold materials, medium temperature mold materials, and low-temperature mold materials. Therefore, what we usually refer to as low-temperature wax and high-temperature wax are clearly distinguished by the thermal stability of the mold material or wax material.

2、 It is determined based on the composition of the matrix material of the mold material.

According to the development of modern molding materials, they can be divided into wax based molding materials, rosin based molding materials, plastic molding materials, water-soluble molding materials, and filling molding materials.

The first classification method seems to be basically consistent in terms of information introduction. However, the latter classification method varies from person to person: some online materials are divided into four categories: wax based molds, resin based molds, filler molds, and water-soluble molds; In fact, no matter how the mold material is divided, it never changes without its roots. Basically, they are all similar. However, modern times have added a new type of mold material for rapid prototyping, which is a new type of mold material.

Next, we will further elaborate on the centralized mold material of the first classification method.

1. Low temperature mold material. The melting point of low-temperature mold materials is generally lower than 70 ℃, with low strength, poor thermal stability (30 ℃), large shrinkage, and a large variation in the size and shape of the mold with room temperature. The surface roughness is relatively coarse. The mold material composed of 50% paraffin and 50% stearic acid commonly used in China is a typical example of this type of mold material. However, this type of mold material has a simple production process, high mold material recovery rate, reusability, and lower cost. Generally pressed in paste form, manually operated, can be dewaxed with hot water. This type of mold material is generally used together with water glass binder.

2. Medium temperature mold material. Mainly rosin wax based and filling molds, with a melting point between 70-100 ℃, high strength, good thermal stability (35 ℃), small shrinkage, good dimensional stability, and fine surface roughness and good replication performance when pressed in liquid form. Reusable, complex production process and high cost. It can be dewaxed with water, steam, or microwave. This type of mold material is generally used in conjunction with silica sol binder. Generally, wax injection machines are used for production.

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