Shot peening to prevent the corrosion cracking of austenitic stainless steels

Journal Article · Fri Jun 01 04:00:00 EDT 1979 · J. Mater. Energy Syst.; (United States)

DOI:https://doi.org/10.1007/BF02833987· OSTI ID:6199541

Friske, W H; Page, J P

Rockwell International and Metal Improvement Company have conducted a joint test program to develop shot peening as a technique for preventing corrosion cracking in austenitic stainless steels. Initial laboratory-scale tests demonstrated the feasibility of preventing stress corrosion cracking by shot peening to impose compressive stresses on the surface of the work pieces. Conventional U-bend test specimens, when peened, survived 1000 h tests in the boiling 42% magnesium chloride stress corrosion test. Unpeened reference specimens commonly fractured within one or two hours in this test. Component tests were conducted to demonstrate the practicality of the peening process for sizes and shapes that typify components in a reactor piping system. Pipe sections and cold worked, hexagonal tubes were tested. In all components, unpeened sections developed stress corrosion cracks within a few hours in the magnesium chloride test; in contrast, the shot peened surfaces survived hundreds of hours. It was discovered at Rockwell International that intergranular corrosion can be prevented in austenitic stainless steels by severe shot peening prior to exposure to sensitizing temperatures. For this purpose, the surfaces must be severely cold worked by the shot peening to break up surface grains and grain boundaries. Two nondestructive testing techniques show promise as methods for measuring the stress or cold work imparted on the surface of the work piece by peening. In one method, eddy currents are used to measure differences in electrical properties induced by cold working of metals. Another method is a magnetic technique which measures the changes in magnetic properties due to the transformation of austenite to ferrite by cold working.

• OSTI ID: 6199541
• Journal Information: J. Mater. Energy Syst.; (United States), Journal Name: J. Mater. Energy Syst.; (United States) Vol. 1:1; ISSN JMSMD
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
220200 -- Nuclear Reactor Technology-- Components & Accessories
36 MATERIALS SCIENCE
360105* -- Metals & Alloys-- Corrosion & Erosion
ALLOYS
AUSTENITIC STEELS
CHEMICAL REACTIONS
CHROMIUM ALLOYS
CHROMIUM STEELS
CHROMIUM-NICKEL STEELS
COLD WORKING
CORROSION
CORROSION PROTECTION
CORROSION RESISTANT ALLOYS
CRACKS
CRYSTAL STRUCTURE
EDDY CURRENT TESTING
ELECTRICAL PROPERTIES
ELECTROMAGNETIC TESTING
FABRICATION
FERRIMAGNETIC MATERIALS
FERRITES
GRAIN BOUNDARIES
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
IRON ALLOYS
IRON BASE ALLOYS
IRON COMPOUNDS
MAGNETIC MATERIALS
MAGNETIC PROPERTIES
MATERIALS
MATERIALS TESTING
MATERIALS WORKING
MICROSTRUCTURE
NICKEL ALLOYS
NIOBIUM ADDITIONS
NIOBIUM ALLOYS
NONDESTRUCTIVE TESTING
NUCLEAR FACILITIES
NUCLEAR POWER PLANTS
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
PIPELINES
POWER PLANTS
SHOT PEENING
STAINLESS STEEL-18-8
STAINLESS STEEL-304
STAINLESS STEEL-321
STAINLESS STEEL-347
STAINLESS STEELS
STEELS
STRESS CORROSION
SURFACE TREATMENTS
TESTING
THERMAL POWER PLANTS
TITANIUM ADDITIONS
TITANIUM ALLOYS
TRANSITION ELEMENT COMPOUNDS