Strength and fracture of uranium, plutonium and several their alloys under shock wave loading

V.K Golubev

doi:10.1051/epjconf/20122602015

Abstract

Results on studying the spall fracture of uranium, plutonium and several their alloys under shock wave loading are presented in the paper. The problems of influence of initial temperature in a range of − 196 – 800∘ C and loading time on the spall strength and failure character of uranium and two its alloys with molybdenum and both molybdenum and zirconium were studied. The results for plutonium and its alloy with gallium were obtained at a normal temperature and in a temperature range of 40–315∘ C, respectively. The majority of tests were conducted with the samples in the form of disks 4 mm in thickness. They were loaded by the impact of aluminum plates 4 mm thick through a copper screen 12 mm thick serving as the cover or bottom part of a special container. The character of spall failure of materials and the damage degree of samples were observed on the longitudinal metallographic sections of recovered samples. For a concrete test temperature, the impact velocity was sequentially changed and therefore the loading conditions corresponding to the consecutive transition from microdamage nucleation up to complete macroscopic spall fracture were determined. The conditions of shock wave loading were calculated using an elastic-plastic computer program. The comparison of obtained results with the data of other researchers on the spall fracture of examined materials was conducted.

Highlights

Studying spall fracture of the samples of uranium and its alloys under shock loading was carried out by various researchers [1,2,3,4,5,6,7,8,9,10,11,12,13]
On the basis of such recording the value of 2.4 GPa was obtained for the spall strength of uranium and the measure of sample spall failure was offered
Metallographic examination of recovered samples was made. It was not noted an obvious influence of material purity on the spall strength of uranium, which was in a range of 1.5–1.9 GPa

Summary

Introduction

Studying spall fracture of the samples of uranium and its alloys under shock loading was carried out by various researchers [1,2,3,4,5,6,7,8,9,10,11,12,13]. Metallographic examination of recovered samples was made It was not noted an obvious influence of material purity on the spall strength of uranium, which was in a range of 1.5–1.9 GPa. The complete spall fracture of samples occurred in the range of loading stresses from 3.5 to 5.3 GPa. In work [7] spall fracture of an alloy of uranium with titanium was studied. In work [11] the samples of an alloy of uranium with titanium 6 mm in thickness were loaded by projectiles 2 mm thick speeded up to velocities of 130–500 m/s.

Materials and procedures

Obtained results

Discussion and conclusions