Study Of The Effect Of Melting Practice On The Fatigue Behavior Of High-Strength Steel
Report Number: ASD TR 61-296
Author(s): Nudelman, Harvey B., Sheehan, John
Corporate Author(s): Armour Research Foundation of Illinois Institute of Technology
Laboratory: Directorate of Materials & Processes
Corporate Report Number: ARF 2172-22
Date of Publication: 1961-11
Pages: 75
Contract: AF 33(616)-6290
DoD Project: 7381
DoD Task: 73812
Identifier: AD0271503
Abstract:
Special C-Al deoxidation practice provided a significant increase in the fatigue properties of an induction-melted Ni-Mo high-strength steel. Prot evaluation of cylindrical R. R. Moore fatigue specimens gave E sub p/UTS ratios of 0.500 and 0.555 at ultimate tensile strength levels of 274 and 200 ksi respectively. Vacuum arc and vacuum induction remelting of the specially deoxidized material reduced the fatigue strength to lower values than that characteristic of standard melting practice. The fatigue properties of vacuum-melted high-purity raw materials were inferior to those prepared by induction melting. The harmful effect of Si additions on the fatigue properties of these steels was related to the sequence of addition; the damage was minimized by adding the Si after the completion of the Al killing treatment. Ni-Mo steels were prepared by standard practice and special C-Al practice and tested in axial fatigue in the notched and unnotched conditions. The resultant scatter was too great to indicate any definite trends.
Provenance: Lockheed Martin Missiles & Fire Control
Author(s): Nudelman, Harvey B., Sheehan, John
Corporate Author(s): Armour Research Foundation of Illinois Institute of Technology
Laboratory: Directorate of Materials & Processes
Corporate Report Number: ARF 2172-22
Date of Publication: 1961-11
Pages: 75
Contract: AF 33(616)-6290
DoD Project: 7381
DoD Task: 73812
Identifier: AD0271503
Abstract:
Special C-Al deoxidation practice provided a significant increase in the fatigue properties of an induction-melted Ni-Mo high-strength steel. Prot evaluation of cylindrical R. R. Moore fatigue specimens gave E sub p/UTS ratios of 0.500 and 0.555 at ultimate tensile strength levels of 274 and 200 ksi respectively. Vacuum arc and vacuum induction remelting of the specially deoxidized material reduced the fatigue strength to lower values than that characteristic of standard melting practice. The fatigue properties of vacuum-melted high-purity raw materials were inferior to those prepared by induction melting. The harmful effect of Si additions on the fatigue properties of these steels was related to the sequence of addition; the damage was minimized by adding the Si after the completion of the Al killing treatment. Ni-Mo steels were prepared by standard practice and special C-Al practice and tested in axial fatigue in the notched and unnotched conditions. The resultant scatter was too great to indicate any definite trends.
Provenance: Lockheed Martin Missiles & Fire Control