توليد پوشش TiC روي فولاد D2 به كمك آسيا كاري مكانيكي

Fabrication of TiC coatings on D2 steel substrate using mechanical milling techniques

در اين پژوهش از آسيا كاري مكانيكي براي نشاندن پودر TiC بر روي سطح فولاد D2 به منظور افزايش سختي سطح استفاده شد. نمونه فولادي به همراه پودر و گلوله ها د رمحفظه آسيا كاري قرار گرفتند. د راين آزمايش توزيع گلوله ثابت و نسبت گلوله به پودر (BPR) 1:20 در نظر گرفته شد و ازنمونه هايي با ابعاد 15×10×25 ميليمتر استفاده گرديد. در طي عمليات آسيا كاري مكانيكي سطح نمونه در معرض ضربات پرانرژي گلوله ها قرار گرفت و ذرات پودر گير افتاده بين گلوله هاي و نمونه به وسيله جوش سرد به سطح پيوند خوردند. نشان داده شد كه به اين روش پوشش TiC مي تواند در مدت زمان كوتاهي دردماي اتاق تشكيل شود. مشخص شد كه ضخامت ، سختي و ساختار پوشش تشكيل شده هب اندازه ذرات اوليه پودر پوشش و زمان آسيا كاري وابسته است و در بازده زماني بين 5 تا 50 ساعت با افزايش زمان آسيا كاري ضخامت پوشش افزايش مي يابد. ضخامت و شكل پوشش در شرايط مختلف به كمك ميكروسكوپ الكتروني روبشي (SEM) مورد بررسي و مقايسه قرار گرفتند.

In this study, mechanical milling procedure was used to deposit TiC powder on D2-steel substrates in order to enhance the surface hardness of the samples. Steel samples accompanying the powder and balls were put inside the milling vial. The distribution of the balls was constant and also ball-to-powder ratio (BPR) was assigned 20:1. In these investigations the dimension of the samples was 25×15×10 mm. During the mechanical milling treatment, surface of the samples was subjected to high-energy impacts of the balls. The entrapped powders among the balls and the sample bonded to the surface by cold welding. It was shown that by this method TiC coatings can be produced in short times at room temperature. It was also found that the thickness, hardness, and the structure of the formed coating are dependent on the primary size of the powders and also on the milling duration. During the time period of 5 to 50 hours, it was observed that the coating thickness is increased by mechanical milling duration. The thickness and appearance of the coating in different conditions were studied and compared by employing scanning electron microscopy (SEM).