From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Stress-strain diagram for pretempered wire steel #7, showing tension and torsion curves.
| Identifier | ExFiles\Box 158\4\ scan0073 | |
| Date | 10th October 1936 guessed | |
| STRESS, THOUSAND LBS. PER SQ. INCH. INCHES ELONGATION TENSION CURVE DEGREES TORQUE TORSION CURVE Figure 10. Stress-Strain Diagram for Pretempered Wire Steel #7. Ultimate strength 203,400 P.S.I. Tension Ultimate strength 184,000 P.S.I. Torsion Elastic Limit 124,000 P.S.I. Tension App. Elastic Limit 110,000 P.S.I. Torsion Elongation 8" 5.0%, 2"—7.8% Reduction of Area 44.7%, Rockwell 42½—43½ C. | ||