Elino Industrie-Ofenbau GmbH, based in Düren, Germany, has supplied custom-heat treatment and sintering equipment since 1933 and more than 4,000 furnaces have been delivered worldwide. The company has recently developed its new “Eco-MIM” batch furnace range for the complete processing of MIM parts. This new system, which the company claims is very energy efficient, has recently been validated and approved.
The approach that Elino has taken with its new system is to develop an Eco-MIM one-step complete debinding furnace, which is designed to work alongside a new Eco-MIM batch sintering furnace. The one-step debinding unit offers catalytic debinding, thermal debinding and pre-sintering up to 900°C with a special convection system offering temperature homogeneity of ± 5°C. A special off gas burner system is installed and different atmospheres (Ar, N₂, H₂, N₂-H₂, and air) can be used during the thermal debinding process, depending on materials selection. Ceramic materials can also be thermally debound in pure air. If required, the system is able to switch to a different protective atmosphere during processing and prior to pre-sintering.
Water or solvent debound parts can be dried in the Eco-MIM debinding furnace at between 80 and 90°C. Different temperature-time profiles can also be defined for the various debinding steps with different atmospheres. Part production, states Elino, can be increased up to three cycles per 24 hours with an air cooling system.
The company states that separate thermal debinding is beneficial for the complete removal of residual binder and results in fewer hydrocarbons contaminating the sintering furnace.
The company’s “Eco-MIM” batch sintering furnace is also claimed to offer cost effective processing and Elino states that the sintering cycle can by shortened by using a fast heating ramp, increasing production to three complete cycles in 24 hours. “Our system results in no condensation, no contamination, no blockages in the vacuum pump and longer muffle life in the vacuum sintering furnace,” stated Elino.
Charge carriers have been designed to fit exactly the same way in both the sintering furnace as in the debinding furnace making the transfer of parts easier.
The company also states that reactive materials such as Ti and Ti alloys can be sintered with fewer impurities under vacuum levels from 10-2 to 10-5 with temperature accuracy of ± 3°C at a maximum 1450°C. Process gases such as Ar, N₂, H₂ and a H₂-N₂ mixture can also be used in the sintering furnace.
Elino has been a manufacturer of continuous debinding and sintering furnaces for MIM for a number of years, with its systems used in a number of countries. The company claims that its continuous MIM furnaces consume less process gas than alternative systems and are amongst the most cost-effective to operate.