مطالعه امكان ساخت و بررسي خواص مكانيكي آهنرباهاي چسبي Nd-Fe-B به روش ساخت بر پايه حلال و ساخت بر پاييه ذوب

Studying the feasibility of composing and investigating the mechanical properties of Nd-Fe-B hybrid magnets, using solvent-base and melting-base approaches

در پژوهش حاضر امكان ساخت آهنرباهاي چسبي Nd-Fe-B به دو روش مورد بررسي قرار گرفت. در روش اول يعني روش ساخت بر پايه حلال، سه نوع چسب مختلف به عنوان زمينه پليمري رد توليد آهنرباهاي با پايه Nd-Fe-B چسبي مورد آزمايش قرار گرفتند. در اين روش به منظور انحلال هر يك از انواع چسبها، حلالهاي متفاوتي مورد آزمايش قرار گرفتند. در روش دوم يعني ساخت بر پايه ذوب، به منظور اختلاط پودر فلزي با زمينه پليمري، نخست پليمر مورد نظر ذوب و به طور كامل با پودر فلزي مخلوط گرديد. سپس مخلوط حاصل به صورت گرانول خرد و بعدا توسط يك دستگاه تزريق ماردوني تزريق گرديد. د رنهايت خواص مكانيكي و مغناطيسي نمونه هاي توليد شده مورد بررسي قرار گرفتند. نمونه هاي توليدي در دماي محيط، به حداكثر استحكام كششي نمي رسد. در دماهاي بالا اثر سختي مواد به عنوان تابعي از كرنش اعمالي، در نمونه هاي با درصد ذرات جامد كمتر بعد از حدود 1 درصد كرنش و در نمونه هاي با درصد جامد بيشتر بعد از حدود 0/1% كرنش قابل حصول است.

Gelcast bodies based on cordierite glass-ceramics were prepared by sintering route. Effect of monomer and cross-linker values as well as sintering temperature on bending strength of dried and sintered bodies were investigated. While the bending strength of dried gelcast bodies was increased with the percentage of the polymers, bending strength of sintered bodies was changed conversely with them. Therefore, it was concluded that the least amount of monomer Acrylamid (3wt.%) and moderate amount of crosslinker(~ 0.75 wt.%) guarantees the required dried and fired bending strengths. The optimum sintering temperature was about 1270°C and specimens that was fired at this temperature showed a maximum bending strength of about 200 MPa. In the recent study, the feasibility of composing the Nd-Fe-B binder magnets by two approaches was investigated. In the first approach (i.e. solvent-base Composing) three different bonds as polymer matrix, were used in producing bonded Nd-Fe-B-based magnets. In this approach, different solvents were used in order to solve each of the bonds. In the second approach (i.e. melting-base composing) the polymer was melted at first and then mixed with the metallic powder, in order to mix the metallic powder and polymer matrix. Then the resulted mixture was crushed into granules and injected by an injection device. After all, the mechanical and magnetic properties of the produced samples were investigated. The samples produced in the room temperature, wouldn’t reach to maximum tensile strength. In higher temperatures, material hardness, as a function of applied strain, was gained in the samples containing lower solid percents and samples containing higher solid percents, after 1% strain and 0.1% strain, respectively.