Cold storage material particles, cold storage, refrigerator, superconducting magnet, nuclear magnetic resonance imaging device, nuclear magnetic resonance device, cryopump, and magnetic field application type single crystal pulling device
PROBLEM TO BE SOLVED: To provide cold storage material particles having excellent characteristics. SOLUTION: The cold storage material particles of the embodiment include a cold storage material having a maximum specific heat of 0.3 J / cm 3 · K or more at a temperature of 20 K or less, calcium (Ca), magnesium (Mg), beryllium (Be), and the like. A first region containing one metal element selected from the group consisting of strontium (Sr), aluminum (Al), iron (Fe), copper (Cu), nickel (Ni), and cobalt (Co). And a second region closer to the outer edge of the cold storage material particles than the first region and having a higher concentration of metal elements than the first region. [Selection diagram] Fig. 1【課題】優れた特性を備える蓄冷材粒子を提供する。【解決手段】実施形態の蓄冷材粒子は、温度２０Ｋ以下における比熱の最大値が０．３Ｊ／ｃｍ３・Ｋ以上の蓄冷物質と、カルシウム（Ｃａ）、マグネシウム（Ｍｇ）、ベリリウム（Ｂｅ）、ストロンチウム（Ｓｒ）、アルミニウム（Ａｌ）、鉄（Ｆｅ）、銅（Ｃｕ）、ニッケル（Ｎｉ）、及び、コバルト（Ｃｏ）から成る群から選ばれる一つの金属元素と、を含み、第１の領域と、第１の領域よりも蓄冷材粒子の外縁に近く第１の領域よりも金属元素の濃度が高い第２の領域とを有する。【選択図】図１
