Jewelry casting mainly includes:
Mechanical stamping, precision casting, and hand-manufacturing
The traditional mechanical stamping method and manual manufacturing method have been difficult to meet the requirements of delicate and complex structure and mass production of jewelry, while the gypsum type precision casting process developed in the 1970s has the following advantages: metal consumption and casting rejection rate are low; The dimensional accuracy and surface finish of the castings are high, and the subsequent procedures are few; the internal quality and mechanical properties of the castings are good; the production process is simplified, and mechanized and automated production is gradually realized; the environmental pollution is small, and the labor environment of the foundry workers is greatly improved. It has become the main technical means for mass production of jewelry at home and abroad.
The jewelry casting process is to mix coagulant, refractory materials, additives and water into a slurry, and pour the slurry into a mold with a wax mold under vacuum conditions. Dewaxing the mold, roasting into a gypsum mold, and finally casting to obtain a complex thin-walled qualified casting. The composition, particle size distribution and expansion and contraction properties of gypsum-type materials are the key factors affecting the quality of jewelry castings.
Jewelry casting process
The gypsum mold used for casting must have the characteristics of thermal shock resistance, low thermal conductivity, good thermal insulation effect, high-definition and accurate reproduction function, self-collapse when immersed in water, and easy demoulding. Its production is the most critical link in the entire jewelry production process.
Among them, the process with the longest time is gypsum sintering. Due to the poor thermal conductivity of gypsum type, the temperature difference between inside and outside is large during roasting, and it is a brittle material. In the process of heating and cooling, thermal stress can easily cause defects such as cracks and surface peeling.
About gypsum powder
Gypsum powder is essentially a refractory material. The function of the refractory material is to offset the shrinkage generated during the dehydration, drying and roasting of the gypsum type, and also to improve the refractoriness of the gypsum type. The refractory material and gypsum are only mechanically mixed without chemical reaction, and the gypsum plays the role of wrapping and bonding the refractory material. Therefore, the strength of the gypsum type is not only related to the performance of the gypsum itself, but also the inlaid state of the refractory material and the gypsum. .
There are many kinds of refractory materials, which have different effects on the performance of gypsum type. Quartz-gypsum mixture requires a large amount of water, the mutual inlaid state is poor, the strength of the mixture is low, the thermal expansion rate and crack tendency are large, the suspension and fluidity of the slurry are poor, and it can only meet the general technical requirements for the production of castings. With kaolin, high alumina bauxite and coal gangue as refractory materials, the stone tone type has high strength, small thermal expansion rate and crack tendency, and is suitable for the production of castings with medium and above technical requirements.
About 311C Jewelry Casting Resin
And ifun311C produced by ifun company is an excellent jewelry casting resin, it has the following characteristics, very good printing, good molding, can print models with complex structure, and ifun311C has a certain rigidity, easy to save, not easy to transport during transportation damage, we have done many tests. If gypsum powder with high strength and high temperature resistance is used, ifun311C will get very good casting effect, which puts forward requirements on the quality of gypsum powder. High-end casting requires high-end gypsum powder. As a result of joint cooperation, many casting resins on the market cannot achieve the same printing effect as 311C, such as jewelry models with a hole diameter of less than 0.3mm. Many casting resins on the market cannot be printed at present, but ifun311C can make small holes perfect. Print it out, this is where the 311C’s strengths lie