MIM Catalytic Degreasing Furnace

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The Catamold method is a one-step degreasing method developed by German BSAF Bloemacher in the early 1990s. It is a catalytic degreasing method.

The main technical feature of the method is the use of polyaldehyde resin as a binder and rapid catalytic degreasing in an acidic atmosphere. The long-chain polyaldehyde resin is used as a binder, and the polarity of the polyacetal resin is used to connect the metal powder, which is suitable for a wide range of powder types. Polyaldehyde resin decomposes into formaldehyde under the catalysis of acidic atmosphere. This decomposition reaction occurs rapidly above 110 °C. It is a direct gas-solid transition, which is beneficial to control the deformation of green body and ensure the dimensional accuracy after sintering.

The catalytic degreasing is carried out at the interface of the atmosphere-binder, and no gas exists inside the shaped compact, and the advancement speed of the reaction interface can reach 1-4 mm/h. CREMER Germany designed a continuous degreasing and system for the Catamold degreasing process by placing the MIM forming in the first heating zone of degreasing and heating to 86 ° C under a nitrogen atmosphere to avoid subsequent catalysis. Nitric acid condenses on the billet during the degreasing process. The shaped body is then moved into a catalytic degreasing zone to decompose the polyaldehyde resin into formaldehyde. After preliminary degreasing, the billet enters the sintering furnace through the first clean room, and the residual binder is removed in the first heating zone of the sintering furnace. Subsequently, sintering is carried out under the action of nitrogen, hydrogen, argon, ammonia decomposition and some other mixture. An important feature of the Catamold method is the use of catalyst degreasing, no liquid phase during degreasing, avoiding the weakness of MIM products that are prone to deformation and dimensional accuracy control. It is a major breakthrough in the MIM industry and is greatly shortened due to catalytic degreasing. Degreasing time, which reduces costs. And the Catamold method can produce larger size MIM components.

With CREMER’s continuous degreasing and sintering system, continuous production can be achieved, making MIM truly a competitive PM near net forming technology.

The Catamold method is currently the most advanced MIM degreasing method used in industrial production. However, this method has problems such as acid atmosphere corrosion equipment, exhaust gas treatment, etc., and equipment investment cost is higher than other methods.

Catalytic degreasing furnace
1. Multiple active and passive safety and explosion protection design, leading the world in safety performance;

2. The unique designed quick degreasing system can greatly improve the degreasing efficiency on the premise of ensuring the uniformity of degreasing;

3. Environment-friendly exhaust gas treatment system ensures that nitrogen oxides in the exhaust gas are reduced and decomposed to meet increasingly stringent environmental emission requirements