ホットプレス法によるMgB2バルクの作製と組織評価

抄録

MgB₂ bulks have been prepared by hot pressing method in order to fabricate high density MgB₂ structure. Mixed Mg and B powder were enclosed in stainless steel mold. The bulk samples were treated at 850°C for 3 h under 30-300 MPa in Ar gas atmosphere. The hot pressed sample size is 20 mm in diameter and 5.6~10 mm in thickness. The XRD patterns of the bulks show that MgB₂ phase is synthesized and dominant with small amount of MgO in the whole range of 0~300 MPa. The density of the bulks increased with increasing hot pressing pressure, and reached a peak of 2.34 g/cm³ at 200 MPa which corresponded to the relative density of 90 %.