A comparative evaluation of low-cycle fatigue behavior of type 316LN base metal, 316 weld metal, and 316LN/316 weld joint
- Indira Gandhi Centre for Atomic Research, Tamil Nadu (India)
A comparative evaluation of the low-cycle fatigue (LCF) behavior of type 316LN base metal, carried out at 773 and 873 K. Total strain-controlled LCF tests were conducted at a constant strain rate of 3 {times} 10{sup {minus}3} s{sup {minus}1} with strain amplitudes in the range {+-}0.20 to {+-}1.0 pct. Weld pads with single V and double V configuration were prepared by the shielded metal-arc welding (SMAW) process using 316 electrodes for weld-metal and weld-joint specimens. Optical microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) of the untested and tested samples were carried out to elucidate the deformation and the fracture behavior. The cyclic stress response of the base metal shows a very rapid hardening to a maximum stress followed by a saturated stress response. Weld metal undergoes a relatively short initial hardening followed by a gradual softening regime. Weld joints exhibit an initial hardening and a subsequent softening regime at all strain amplitudes, except at low strain amplitudes where a saturation regime is noticed. The initial hardening observed in base metal has been attributed to interaction between dislocations and solute atoms/complexes and cyclic saturation to saturation in the number density of slip bands. The 18-8 group of austenitic stainless steels, such as AISI type 316, 304, and their modified grades, finds applications as structural material for various components of the liquid-metal-cooled fast breeder reactor (LMFBR).
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 72789
- Journal Information:
- Metallurgical Transactions, A, Vol. 26, Issue 5; Other Information: PBD: May 1995
- Country of Publication:
- United States
- Language:
- English
Similar Records
Influence of weld discontinuities on strain controlled fatigue behavior of 308 stainless steel weld metal
Effect of heat treatment on Type 316 stainless steel weld metal