8-12 November 2020
Schönbrunn Palace - Apothekertrakt, Vienna/Austria
Europe/Vienna timezone
Home > Timetable > Session details > Contribution details

Contribution Poster

Schönbrunn Palace - Apothekertrakt, Vienna/Austria
Press Hardening of Coated Steels

CORROSION RESISTANCE OF VARIOUS METALLIC COATING ON HOT PRESS FORMING (HPF) STEEL

Speakers

  • Hyeon Seok HWANG

Primary authors

Co-authors

Content

Hot press forming (HPF) steel has been widely used to produce high strength and complex shaped car parts because it provides high mechanical properties and formability. Process of press hardening is carried out at high temperature over A3 line, which cause the oxidation of the steel surface. Since oxide removal is required for welding and painting, many different coatings have been introduced to suppress oxide formation. The aluminum coating is widely used and commercially successful. However, its low cathodic protection causes cosmetic and perforation corrosion of HPF steel. The Zn and AlZn based coatings are developed to enhance the resistance of corrosion. Galvanized steel is effective for suppressing corrosion, but the occurrence of microcrack is unavoidable. To maintain resistance of corrosion and microcrack, Al-Zn-Si coating on HPF steel has been developed in laboratory and validated through pilot plant. This paper demonstrates the excellent anticorrosive effect of the newly developed coating layer. After heat treatment of press hardening, Ecorr of the Al-Zn-Si coating was similar to the Ecorr of Zn-HPF. The coating layer containing zinc was shown to be beneficial in cathodic protection. This new coating shows that reduced corrosion of steel compared to AlSi HPF and improved spot weldability without additional shot-blasting. In addition, liquid metal embrittlement and microcracks caused by the zinc containing layer were not observed

PhD work

no it isn't

Speaker Country

South Korea (ROK)

Keywords

AlZn HPF PHS corrosion