Design of strong, ductile, HSLA and dual phase steels

Conference · Wed Jan 01 00:00:00 EST 1986

OSTI ID:5821002

Thomas, G

This paper summarizes our alloy design programs at Berkeley which utilize the concept of two-phase steels as a means of optimizing these mutually exclusive properties. The underlying principle here is to design composite microstructures whereby the advantages of the second phase are optimized while the less desirable features of this phase are simultaneously mitigated by the presence of the other constituent phase. The size, distribution, shape and volume fraction of the second phase critically control the mechanical properties, especially fracture and fatigue of the dual phase systems. As a consequence, these structures offer a degree of metallurgical flexibility that is absent in single phase structures or in many precipitation strengthened systems, for attaining optimum sets of mechanical properties. Examples are presented here of martensite/austenite (approx.2 to 5%) mixtures designed for optimum combinations of high strength, toughness, and wear properties in medium carbon steels, e.g., for mining and agricultural applications, and martensite/ferrite (approx.80%) structure for high strength, cold formability and improved low temperature ductility in low carbon steels. Applications to sheet, line pipe rods and wires will be demonstrated for the latter class of steels.

• Research Organization: Lawrence Berkeley Lab., CA (USA)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 5821002
• Report Number(s): LBL-21303; CONF-860174-1; ON: DE86011313
• Resource Relation: Conference: 1. Indo/US workshop on iron and technology, Ranchi, India, 6 Jan 1986; Other Information: Portions of this document are illegible in microfiche products
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CARBON STEELS
MECHANICAL PROPERTIES
MICROSTRUCTURE
OPTIMIZATION
AUSTENITE
FATIGUE
FRACTURE PROPERTIES
MARTENSITE
WEAR
ALLOYS
CARBON ADDITIONS
CRYSTAL STRUCTURE
IRON ALLOYS
IRON BASE ALLOYS
STEELS
360103* - Metals & Alloys- Mechanical Properties
360102 - Metals & Alloys- Structure & Phase Studies