logo
 
Title STATISTICAL OPTIMIZATION OF THE MECHANICAL PROPERTIES OF HEAT TREATED ALUMINUM BRONZE (CU-10%AL) USI
Journal International journal of Engineering And Applied Science
Publisher Faculty of Engineering, Nnamdi Azikiwe University, Awka Nigeria.
Issue 1
ISSN 1119-8109
Pages 69-92
Subject Metallurgical Engineering
Date of Publication 2017

AUTHOR(S) FA Anene1, NE Nwankwo1 and VU Nwoke1

ABSTRACT

Mathematical models have been derived for the prediction of the mechanical properties (Ultimate tensile strength (UTS), Yield Strength and %Elongation) of heat treated Aluminum bronze alloy. The aim of the research is to improve on the mechanical properties of the alloy using ageing heat treatment. The selected heat treatments were Solutionizing, Quenching and Ageing. Response Surface Methodology (RSM) was employed to investigate the influence of the process variables (ageing temperature and soaking time) on the mechanical properties. The two level-2 factor Central Composite Design (CCD) used in this study required 13 experiments. The cast specimens were solutionized at 900℃ for 1hr, quenched in water and then aged at temperatures of 109℃, 150℃, 250℃, 350℃ and 391℃, soaked for 5min, 25min, 73min, 120min and 140min respectively, according to the experimental design. The best combination of mechanical properties was achieved at ageing temperature of 350℃ and soaking time of 120mins which gave 565MPa for UTS, 480MPa for Yield Strength and 17.8%E. A model following a second order Polynomial which includes interaction terms was used to calculate the predicted responses. The models include:𝑼𝑻𝑺=𝟐𝟕𝟏.𝟔𝟏+𝟏.𝟓𝟔𝟏𝑿𝟏+𝟎.𝟕𝟕𝟔𝑿𝟐+{𝟏.𝟕𝟑𝟕𝑿𝟏𝑿𝟐−𝟑.𝟎𝟓𝟖𝑿𝟏𝟐−𝟑.𝟐𝟒𝟕𝑿𝟐𝟐}×𝟏𝟎−𝟑 𝒀𝑺=𝟐𝟑𝟓.𝟕+𝟎.𝟕𝟐𝟔𝑿𝟏+𝟎.𝟖𝟖𝟎𝟗𝑿𝟐−𝟖.𝟏𝟏𝟑×𝟏𝟎−𝟒𝑿𝟏𝟐−𝟑.𝟎𝟒𝟏𝟔×𝟏𝟎−𝟑𝑿𝟐𝟐 %𝑬=−𝟎.𝟑𝟓𝟒𝟖+𝟎.𝟎𝟕𝟎𝟗𝑿𝟏+𝟎.𝟏𝟐𝟗𝟓𝑿𝟐−𝟐.𝟑𝟏𝟓𝟖×𝟏𝟎−𝟒𝑿𝟏𝑿𝟐−𝟓.𝟖𝟏𝟕𝟓×𝟏𝟎−𝟓𝑿𝟏𝟐−𝟑.𝟎𝟒𝟏𝟔×𝟏𝟎−𝟑𝑿𝟐


Keywords: Response Surface Methodology, Optimization, Solutionizing, Quenching and Ageing.




Home | About Us | Journals | e-Newsletter | Advertise | Update | Subscribe | Contact Us | Webmaster
Welcome To Journal of Engineering and Applied Science.