Enhanced Powder Metal Materials for Exhaust System Applications

Property test data shows 434 stainless steel material, with and without nickel additions, to be a desirable material for exhaust system component applications. The material provides a good balance of corrosion and oxidation resistance, impact strength, and tensile strength compared to other 400 series stainless steel powder metal (P/M) materials. Addition of nickel to standard 434 greatly improves many physical properties with a slight increase in cost. Parts with densities between 7.2 and 7.5 g/cc offer the best combination of properties versus process economics. The processing costs to achieve high densities are minimized when the parts are sintered at temperatures at or above 2400°F, thus eliminating the need for a secondary operation such as coining or heat treating.