Abstract

High-strength ferritic stainless steel HSS430CU has been developed as a material for use in catalytic converters. This material has superior strength at elevated temperatures and excellent press-forming properties.HSS430CU does not contain the expensive element Mo that is normally added to the conventional high-strength ferritic stainless steel that is represented in Type444. Instead, Cu is added, which achieves equal or better high-strength properties. This material combines both the workability and strength properties required for catalytic converters. These properties are achieved as follows: superior workability is ensured byincorporating Cu, which is required for high strength, into solid solution when the materials are still raw materials, prior to press-forming; and high strength is ensured once the part is mounted in the vehicle, when heat energy is received as a result of exhaust gas, causing the Cu that was incorporated into solid solution to precipitate as fine ε-Cu crystals.When this material was used in the catalytic converter for the 2014 model year FIT, the high-strength-providing properties of the material were utilized to reduce the plate thickness by 20% or greater. In addition, that superior workability enabled parts that had previously been formed as two pieces to be integrated into one piece, and it reduced weight while simultaneously cutting costs as well.

References

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Author (organization or company)

• Osamu SUZUKI（Automobile R&D Center）

Publication Information

Article of Honda R&D Technical Review Vol.26 No.1 (64 - 70)

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