Accession Number : AD0763201

Title :   A Phenomenological Description of Central Burst Formation During Hydrostatic Extrusion.

Descriptive Note : Technical rept.,

Corporate Author : WATERVLIET ARSENAL N Y

Personal Author(s) : Pepe,Joseph

Report Date : MAY 1973

Pagination or Media Count : 46

Abstract : A detailed metallographic investigation of the phenomenological development of central burst defects during hydrostatic extrusion was conducted. The characteristic extrusion pressure versus billet-displacement curve of extrusions containing center burst defects was periodic; each periodic segment consisted of a constant pressure part during which the extrusion velocity was slow followed by a decreasing pressure part during which the extrusion velocity was rapid. It was established that during the part of the cycle exhibiting slow billet movement, near the billet centerline beyond the end of the die deformation zone, small microcracks formed, linked-up by tensile fracture and formed a rather large cone shaped defect exhibiting little crack opening displacement. (Modified author abstract)

Descriptors :   (*EXTRUSION, DEFECTS(MATERIALS)), HYDROSTATIC PRESSURE, RUPTURE, STEEL

Subject Categories : Metallurgy and Metallography
      Fabrication Metallurgy

Distribution Statement : APPROVED FOR PUBLIC RELEASE