بهبود خواص مكانيكي فولاد AISI1045 در سنك زني HEDG با استفاده از بهينه سازي متغيرهاي فرايند

Mechanical properties improvement of steel AISI1045 in High Efficiency Deep Grinding by process parameter optimization

از مشكلات روش هاي ماشينكاري از جمله روش سنگ زني (High Efficiency Deep Grinding) HEDG حرارت اعمال شده به قطعات و باقيماندن تنش پسماند روي سطح آنها است. از اين رو هدف اين تحقيق بهينه سازي فرآيند است تا با در نظرگرفتن حالت بهينه اي از فرآيند، حرارت و تنش ها ي پسماند كاهش يافته و از طرفي استحكام و سختي سطح فولاد افزايش يابد. در اي ن مرحله با استفاده از روش تاگو چي، آزمايشهاي لازم براي گرفتن نتيجه قابل اطمينان طراحي شده و شرايط بهينه فرآ يند بدست آمد . نتا يج نشان ميدهد كه با بهينه سازي پارامترها حرارت و تنش پسماند كششي كاهش يافته و سخ تي بالا م يرود. از طرفي صحت اين موضوع، با اندازهگيري و تحليل سختي و مقايسه آنها با نتايج تحلي ل المان محدود و نتايج تجربي مورد بررسي قرار گرفت و مشاهده شد كه مطابقت خوبي بين نتايج وجود دارد.

The major problem about material removal process specially grinding is heat during process and hence residual stress in the surface of product. Therefore optimization of HEDG process is the main goal of this study in order to reduce heat and residual stress and also increase strength and hardness of annealed steel AISI1045 by considering an optimized state of process. In other words, the effects of main parameters e.g. depth of cut, wheel speed, work piece speed and cross feed on surface temperature, surface integrity and quality and residual stress has been studied. During this, the essential experiments were been designed to achieve reliable results by Taguchi method and then the best process conditions will be available. The results demonstrate that reduction of surface temperature and compressive residual stress and also increasing of hardness as optimum process conditions are applied. Beside this, the results will be validated by measuring and analyzing of surface hardness. The obtained results have been compared with Finite Element Method simulation which has been carried out, and with previous corresponded results and consequently observed that good agreement has been found between the FE results and experimental observations.