Microstructure and properties of high strength aluminium alloys subjected to rapid solidification processing

Abstract

High strength aluminium alloys of 7075 type, modified by the addition of 1.0 wt% Fe, Mn, or Ni were rapidly solidified (RS) by centrifugal atomization and substrate quenching. The product was in the form of circular platelets of 3-5

<span style="font-size:14.0pt;line-height:115%;font-family:" times="" new="" roman";="" mso-fareast-font-family:"times="" roman";color:black;mso-ansi-language:en-in;="" mso-fareast-language:en-in;mso-bidi-language:hi"="" lang="EN-IN">mm diameter and 20-50 <span style="font-size:14.0pt;line-height:115%;font-family:" times="" new="" roman";="" mso-fareast-font-family:hiddenhorzocr;color:black;mso-ansi-language:en-in;="" mso-fareast-language:en-in;mso-bidi-language:hi"="" lang="EN-IN">μm <span style="font-size:14.0pt;line-height:115%;font-family:" times="" new="" roman";="" mso-fareast-font-family:"times="" roman";color:black;mso-ansi-language:en-in;="" mso-fareast-language:en-in;mso-bidi-language:hi"="" lang="EN-IN">thick and solidified at a cooling rate of <span style="font-size:14.0pt;line-height: 115%;font-family:" times="" new="" roman";mso-fareast-font-family:hiddenhorzocr;="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">≥<span style="font-size:14.0pt;line-height:115%; font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">10⁴ <i>°</i>C/s<i>. </i>Microstructural study of the RS alloys revealed some novel features like bimodal morphology and spiral morphology. The RS platelets were consolidated by compacting, vacuum heat treatment and hot extrusion. The consolidated alloys had good surface finish and exhibited moderate improvement in properties.</span></span></span></span></span>