EFFECT OF TEST BAR DESIGN ON MECHANICAL PROPERTIES IN CAST LEAD-TIN BRONZE.

Abstract

A study was made of the solidification behavior of lead-tin copper-base alloys, as affected by the dimensional and volume relationships of the mold, in order to assure a design which would produce a sound and representative test bar. Experimental design modifications were made to the Federal Test Method Standard No. 151a vertical full-web test bar mold. Tests were conducted using tin bronzes of Compositions 2, 4, 5, 8, and 12 of Federal Specification QQ-B-1005, and Composition A of Federal Specification QQ-B-726, Manganese Bronze. Optimum mechanical properties were obtained by using a 3/8 inch web for Composition 2, 4, 8, and 12 while a 3/16 inch web showed the best results with Composition 5. A 3 inch high riser with a volume of 27 cubic inches provided the best mechanical properties with Composition 5. The rate of temperature drop in the metal and the sequence in which freezing occurred at different mold locations was obtained by tracing cooling curves with a recording potentiometer connected to thermocouples inserted into mold cavity at these locations. (Author)

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1967
Accession Number
AD0651267

Entities

People

  • Wade C. Wurtz

Tags

DTIC Thesaurus Topics

  • Cooling
  • Critical Temperature
  • Experimental Design
  • Freezing
  • Glass Transition Temperature
  • Manganese
  • Mechanical Properties
  • Metals
  • Potentiometers
  • Sequences
  • Solidification
  • Specifications
  • Standards
  • Test Methods
  • Thermocouples
  • Transition Temperature

Readers

  • Aerospace Test and Evaluation
  • Electrical Engineering
  • Surface Engineering/Surface Coating Technology.