{"paper":{"title":"Comparative Study of Dense Bulk MgB$_2$ Materials Prepared by Different Methods","license":"","headline":"","cross_cats":[],"primary_cat":"cond-mat.supr-con","authors_text":"A. G\\\"umbel, A. Handstein, A. W\\\"alte, D. Hinz, G. Fuchs, I.E. Kostyleva, J. Eckert, K.-H. M\\\"uller, K. Nenkov, L.N. Bogacheva, L. Schultz, O. Gutfleisch, V. N. Narozhnyi","submitted_at":"2002-06-26T13:51:13Z","abstract_excerpt":"We report on the results of a comparative investigation of highly dense bulk MgB$_2$ samples prepared by three methods: (i) hot deformation; (ii) high pressure sintering; and (iii) mechanical alloying of Mg and B powders with subsequent hot compaction. All types of samples were studied by ac-susceptibility, dc-magnetization and resistivity measurements in magnetic fields up to $\\mu_0H=160$ kOe. A small but distinct anisotropy of the upper critical field $H_{c2}^{a,b}/H_{c2}^{c}\\sim1.2$ connected with some texture of MgB$_2$ grains was found for the hot deformed samples. The samples prepared by"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"cond-mat/0206513","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}