The study of adiabatic shear band instability in a pearlitic 4340 steel using a dynamic punch test

Journal Article · Tue Nov 01 00:00:00 EST 1994 · Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (United States)

DOI:https://doi.org/10.1007/BF02648867· OSTI ID:6895901

Zurek, A K ^[1]

---

1. Los Alamos National Lab., NM (United States)

At low strain rates and moderate levels of strain, slip and twinning are the most common deformation mechanisms in metals and alloys. Both mechanisms are highly correlated with the crystallography of the material. At higher strain rates and levels of strain, deformation instabilities, such as adiabatic shear bands (ASB), may develop. These bands are planar in nature, and their formation is related more to the specimen geometry, deformation process, and mechanical properties of a material than to its local crystallography. The formation of adiabatic shear band instabilities in a pearlitic 4340 steel using a dynamic punch test has been studied. The dynamic punch-impact test produced white-etching adiabatic shear bands. The average strain of 0.5 was sufficient to produce adiabatic shear bands in this steel at an average strain rate of 18,000 s[sup [minus]1]. Nanohardness variations found across the adiabatic shear at an average strain rate of 18,000 s[sup [minus]1]. Nanohardness variations found across the adiabatic shear band are thought to be caused by the fragmentation and spheriodization of the Fe[sub 3]C and the overall deformation and work hardening of the pearlitic microstructure. The cracks formed at the termination of the adiabatic shear band caused the sample to fracture in a ductile mode.

• OSTI ID: 6895901
• Journal Information: Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (United States), Vol. 25:11; ISSN 0360-2133
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
STEELS
DEFORMATION
MICROSTRUCTURE
FRACTURE MECHANICS
HARDNESS
IMPACT TESTS
IRON CARBIDES
ALLOYS
CARBIDES
CARBON COMPOUNDS
IRON ALLOYS
IRON BASE ALLOYS
IRON COMPOUNDS
MATERIALS TESTING
MECHANICAL PROPERTIES
MECHANICAL TESTS
MECHANICS
TESTING
TRANSITION ELEMENT COMPOUNDS
360103* - Metals & Alloys- Mechanical Properties
360102 - Metals & Alloys- Structure & Phase Studies