STRESS-CORROSION CRACKING OF HIGH-STRENGTH ALLOYS
Abstract
Susceptibility to stress-corrosion failure was found in all 18%- nickel alloy heats having yield strengths from 181.5 to 232.2 ksi. Susceptibility became greater with increasing titanium content and yield strength. At a given strength level, 18%-nickel maraging steel was less susceptible to failure than was H-11 steel or a hotworked die steel. Cold working of 18%-nickel maraging steel before aging further reduced its susceptibility to stress-corrosion failure. Distilled water was a more severe exposure medium than 3%-salt water in causing corrosion cracking, and the U-bend test was more severe than the bent-beam test - at least with regard to 18%- nickel maraging steel. The 18%-nickel maraging steel showed a marked increase in susceptibility to stress-corrosion cracking with an increase in environmental temperature. An inhibited epoxy coating designated as 454-1-1 was very effective in greatly delaying stress-corrosion cracking both of maraging steels and of H-11 steel. An inorganic zinc coating designed to impart cathodic protection was found to be ineffective. An electrochemical mechanism for failure of maraging steel in 3%-NaCl solution was demonstrated by the preventing of stress-corrosion failure upon application of cathodic current.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1964
- Accession Number
- AD0604750
Entities
People
- Allan M. Rubin
Organizations
- Aerojet Rocketdyne Holdings