1. Table (1) 6066,6063 ,1050 component elements
Positron Annihilation & Micro-Hardness Measurement of 6063 and 6066 with Compromise with ingot Al M. A. Abdel-Rahman, Alaa El-deen A. El-Nahhas and Emad A. Badawi Faculty of Science, Physics Dept., El-Minia University P.O El-Minia , Egypt
Abstract
The aim of this work is to study the Resistance of this type of alloy to quenching. Hardness measurement can be defined as macro-, micro- or nano- scale according to the forces applied and displacements obtained also study this effect with one of the nuclear techniques( PALT) positron annihilation lifetime technique.
Introduction
Aluminum alloys are used in engineering design chiefly for their light weight, high strength-to-weight ratio, corrosion resistance, and relatively low cost. Aluminum is available in various compositions, including “pure” metal, alloys for casting, and alloys for the manufacture of wrought products. Wrought Alloys. Most aluminum alloys used for wrought products contain Less than 7 percent of alloying elements. By the regulation of the amount and type of elements added, the properties of the aluminum can be enhanced and its working characteristics improved.
6xxx - Al-Mg-Si Alloys The 6xxx wrought alloys are heat treatable, and have moderately high strength coupled with excellent corrosion resistance.
Hardness: The hardness is defined as the "Resistance of metal to plastic deformation, usually by indentation. It is the property of a metal, which gives it the ability to resist being permanently, deformed (bent, broken, or have its shape changed), when a load is applied.
Positron annihilation spectroscopy:
positron annihilation spectroscopy (PAS) may be considered as a method for studying the electronic structure, determining the structure, nature, and concentration of point and extended defects, and investigating the disrupted surface layers and surface states in metals, alloys, semiconductors, ionic crystals, and other substances that have firmly established themselves in the physics and chemistry of solids.
Alloy Al Si Mg Cr Cu Fe Mn Ti Zn
6066
93-97
0.4
0.5
0.2
0.25
6063
97.5
0.1
0.35
1050
99.5
0.05
Table (1) 6066,6063 ,1050 component elements
Positron Lifetime Technique
scpositron lifetime spectrum was accumulated for a period of three hours and all The measurements were repeated three times using 22Na source. For each spectrum about from 5 105 to 6 x 105 coincidence counts were accumulated. Lifetime spectra were analyzed as a single or two lifetime components by using the PATFIT program.
thematic diagram for the detection of the 2-γ positron annihilation
Results
The first observe the changes of the Vicker hardness
values with different forces applied, figure 2 represents
this relation for different alloys (6066, 6063, and 1050).
We see in this figure there are approximately no changes
in Hv with the force. Figures 3,4,5 describes the
relations between The Hardness (□) And The Mean Lifetime (●)
As a functions In the Quenching Temperature
Experimental Procedures:
Sample preparation
Firstly we cut the specimens from a rod of 2024 alloy with the required dimensions (1.5x1.5x0.18 cm3) by using a precision cut off machine (Minitom) running at low speed, which illustrated below.
The second step after cutting is grinding, during grinding the opportunity of minimizing mechanical surface damage that must be removed by subsequent polishing. We grind the surface of the specimens with silica carbide grinding papers of size 220, 500, 800, 1000 and 1200 grit.
This research was conducted using wrought 6xxx series aluminum rods 6066 , First we annealed the samples to 450c to remove internal stresses
Vickers Hardness Test
It is the standard method for measuring the hardness of metals, particularly those with extremely hard surfaces: the surface is subjected to a standard pressure for a standard length of time by means of a pyramid-shaped diamond. The diagonal of the resulting indention is measured under a microscope.
Conclusions
From the above results, we can conclude that the following items:-
The applied force has no real effect on the values of the hardness values.
alloys 6066 , 6063 are a heat treatable alloy but 1050 is not a heat treatable alloy, so
it is Hv does not affected by the changes in quenching temperature.
(6066) heat treatable alloy is more affected by the heat treatment than (6063) alloy which is related to the structure of these alloys since 6066 alloy has Si and Mg much more than 6063 alloy
Hv values vary ( ) for 6063 alloy, while ( ) for 6066 alloy, in camper with ingot alloy (1050)vary from ( ).