Abstract

Friction stir welding was carried out under different heat input and cooling rates to produce lap joints between high strength martensitic steel sheets. the microstructure of the welds was characterized, and microhardness was evaluated. Joint efficiency was determined by lap shear test. Variation in processing conditions governed total heat input, peak temperature and cooling rate during friction stir welding. Weld nugget microstructure depended principally on cooling rate. the slowest cooling rate promoted ferrite-pearlite and the fastest cooling rate resulted in martensite formation in the weld nugget. the weakest region of all the joints was the heat affected zone, which consists of ferrite with small quantities of pearlite. Fracture during shear testing occurred along the heat affected zone of welded joints. the width and grain size of ferrite in heat affected zone controlled the joint efficiency. © 2011 Elsevier B.V.

Department(s)

Materials Science and Engineering

Comments

Missouri University of Science and Technology, Grant None

Keywords and Phrases

Friction stir welding; Hardness; Martensite; Steel

International Standard Serial Number (ISSN)

0921-5093

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2024 Elsevier, All rights reserved.

Publication Date

01 Jan 2011

Included in

Metallurgy Commons

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