2nd International Conference on Production and Industrial Engineering CPIE- 2010 1 Abstract: IS 737 grade Aluminum alloy is extensively used in industries especially automobile due to its low weight. But this material is poorly formable and weldable. That is the reason this material is not used in certain application although it is having superior characteristic of making light weight assemblies. In the present investigation the material is drawn at elevated temperature and its formability was investigated in warm condition and it was found that there was substantial increase in the formability of IS 737 40800 grade material when drawn at 350 0 C. The sensitivity index value is calculated by jump test. These tests were conducted in the plastic region where stress – strain curves are uniform. It is observed that by increasing the temperature of specimen there is an increase in the value of ‘m’ because of increase in plasticity of material. Thickness strains were also calculated and it was found that by increasing the temperature of the material up to 350 0 C, these strains were more uniform. Key words: Aluminum alloy; warm forming; sensitivity index; formability. 1. INTRODUCTION Aluminum although very ductile but it is having very poor formability which restricts its use in most of the industrial applications which requires forming e.g. automobile engineering. In recent years there is a effort to increase the material formability by increasing the temperature of material before and during forming. Bolt et al. [1] applied coupled FEM for simulating the warm sheet forming process of Aluminum alloys using the commercial code MARC. They concluded that, compared to experiments, numerical simulation results underestimated the punch load versus stroke. In their study, DEFORM 2D and 3D, coupled thermo-elastic-visco-plastic commercial FEM codes have been used to analyze warm forming of Magnesium alloys. They reported that the predicted drawability of cylindrical cups was in good agreement with the corresponding results. Lee et al., [2] investigated the warm formability of a commercial Mg-Al-Zn alloy. The relationship between strain rate and formability was used to predict the failure occurred on square cup deep drawing. The measured flow stresses from 200 0 C to 400 0 C were used in FEM analysis for square cup drawing. Toros et al [3] investigated on Aluminum–magnesium (Al–Mg) alloys (5000 series). They observed that formability and the surface quality of the final product of these alloys are not good if processing is performed at room temperature, after the tests in warm conditions the formability of these alloys is increased at temperature range from 200 to 300 °C and better surface quality of the final product has been achieved. Li et al, [4] investigated that as the forming temperature increases under the given tooling geometry, the values of strength coefficient (K) and hardening exponent (n) of aluminum alloys generally decrease and behavior of three aluminum sheet alloys, Al 5182+1% Mn, Al 5754 and Al 6111-T4, are studied in the warm forming temperature range of 200–350 °C and in the strain rate range of 0.015–1.5 s −1 . The total elongation in uniaxial tension is found to increase with increasing temperature and to decrease with increasing strain rate. Li et al, [5] investigated that the formability for all the three Aluminum alloys (Al 5754, Al 5182+1%Mn and Al 6111- T4) improves at elevated temperatures, the strain hardened alloys Al 5754 and Al 5182+Mn show considerably greater improvement than the precipitation hardened alloy Al 6111-T4. Lee is confirmed by post-forming tensile test results that rapid warm forming in the above-mentioned temperature range does not create a significant loss in yield strength. Temperature effect on drawing of the sheet was found to have a large effect on formability. Setting die temperature slightly higher than punch temperature was favorable in promoting formability. Patrick et al., [6] investigated that the under warm forming process is intended to alleviate complex shapes by using an elevated forming temperature which is below the recrystalization . Recently author [7-8] investigated the formability of extra deep drawing (EDD) steel at elevated temperature and it was found that there was drastic increase in the formability of material when the temperature of the material increases. Since aluminum IS 737 40800 grade material is very important due to its commercial use, so in the present Characterization and formability of aluminum IS 737 40800 grade material at elevated temperature Swadesh Kumar Singh 1 *, M L Kranti Raj 1 , SM Hussaini 2 and Amit Kumar Gupta 2 1 Deptt. of Mechanical Engineering, GRIET, Bachupally, Hyderabad, AP, India – 500090 2 Deptt. of Mechanical Engineering, BITS Hyderabad Campus, India *Corresponding author: Email ID: swadesh@iitdalumni.com Tel. +9140-23042555, Fax. +09140-23040860