Title:
BLACK SURFACE COATED HIGH STRENGTH MOLTEN Zn-Al-Mg-BASED PLATED STEEL SHEET FOR AUTOMOBILE COMPONENT EXCELLENT IN FLEXURE PROCESSABILITY AND AUTOMOBILE COMPONENT USING THE SAME
Document Type and Number:
Japanese Patent JP2018145506
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To provide a black surface coated high strength molten Zn-Al-Mg-based plated steel sheet for automobile component having tensile strength of 780 MPa or more, suppressed manufacturing cost, improved strength and flexure processability, and rich in corrosion resistance, and an automobile component using the same.SOLUTION: There are provided a black surface coated high strength molten Zn-Al-Mg-based plated steel sheet for automobile component, having a molten Zn-Al-Mg-based plated layer on a surface of a raw material steel sheet with a prescribed chemical composition, and having brightness of a surface L* of 60 or less and excellent in flexure processability with tensile strength of 780 to 1100 MPa, in which a single phase of a bainitic ferrite phase or a ferrite phase with dislocation density of 1.8 to 5.7×10/mor a phase containing both phases is a main phase, area percentage of a hard second phase and cementite is 3% or less, carbide containing Ti with average particle diameter of 20 nm or less is dispersed and deposited and black oxide of Zn is dispersed in a molten Zn-Al-Mg-based coating layer having a specific composition at diffusible hydrogen concentration of 0.30 ppm or less, and an automobile component using the same.SELECTED DRAWING: Figure 1
Inventors:
FUJIWARA SUSUMU
UESUGI SHINYA
SHIGETOMI TOMOHARU
UESUGI SHINYA
SHIGETOMI TOMOHARU
Application Number:
JP2017044007A
Publication Date:
September 20, 2018
Filing Date:
March 08, 2017
Export Citation:
Assignee:
NISSHIN STEEL CO LTD
International Classes:
C22C38/00; C22C18/00; C22C18/04; C22C38/14; C23C2/06; C23C2/26