Effect of Whiskers and Small Particles on the Deformation and Recrystallization Texture of Aluminium

N Hansen,D Juul Jensen,Y L Liu

doi:10.1155/tsm.14-18.835

Abstract

The effect of small Al2O3 particles (d < 0.1 μm) and of a mixture of Al2O3 particles and SiC-whiskers on the cold-rolling and on the recrystallization texture of aluminium has been studied by neutron diffraction. It has been observed that the strength and the relative intensity of the main rolling components in the deformation texture are affected both by small particles and by introduction of SiC whiskers. In the recrystallized state very different textures have been found ranging from a weak cube texture to a strong {100} (N-texture). The measured textures are related to the size of the recrystallized grains in a discussion of the effect of small particles and whiskers on deformation microstructures and nucleation and growth processes.

Highlights

Large particles and small particles (< 0.1/m) affect the deformation and reerystallization texture of aluminium both when they are present separately or as a mixture[1,2,3,4]. This effect is important to many conventional aluminium alloysbut to the newly developed metal-matrix composite containing large particles or whiskers
Besides the S the Cu component strengthens with increasing A1203 content in the reinforced materials
The reasons given are a) that small particles may homogenize the deformation pattern thereby reducing the amount of structural inhomogeneities which can cause a spread in the texture and b) that coarse particles may be the origin of local lattice rotations[7] thereby causing a spread in the texture

Summary

INTRODUCTION

Large particles (diameter > 0.1-1/m) and small particles (< 0.1/m) affect the deformation and reerystallization texture of aluminium both when they are present separately or as a mixture[1,2,3,4]. This effect is important to many conventional aluminium alloysbut to the newly developed metal-matrix composite containing large particles or whiskers. In the present study the base materials were two aluminium alloys containing different volume fractions of small AI203 particles. After consolidation about 60 and 80 vol% of the whiskers in the MD105 and MD201 material, respectively were present in dusters with sizes ranging from 0.5 to 5/m. For the texture measurements the recrystallized materials were cold rolled to 90% reduction in thielmess and furnace annealed to complete reerystallization. It has to be noted that the strength but not the type of the reeystallization textures are strongly influenced by the heating rate and annealing temperature. This is described in detail elsewhere in these proceedings[6]. The textures are presented by ODFs calculated according to the series expansion method. 2 _< 22 and only even terms are included in the calculations

Deformation Textures

Recrystallization Textures

DISCUSSION