Residual Stress and Stress Corrosion Cracking in the Vicinity of the Expanded Joint of Aluminum Brass Tube Condensers

Abstract

Summary:The residual stress and stress corrosion cracking of aluminum brass condenser tubes were studied by means of strain meter and stress corrosion cracking test.The following aspects have been observed.(1) Large tensile stress remains on the inner surface of the brass tube in the vicinity of the expanded tube joint.(2) The stress has a relationship with the clearance between tube and tube sheet before the expanding operation.(3) Closely fitted test pieces reduced the stress and showed good results in stress corrosion cracking test using aqueous ammonia.