The Vickers hardness of polycrystalline {\gamma}-B was measured using adiamond indentation method. The elastic properties of polycrystalline{\gamma}-B (B=213.9 GPa, G=227.2 GPa, and E=503.3 GPa) were determined usingultrasonic measurement at ambient condition. Under the loading force up to 20N, our test gave an average Vickers hardness in the asymptotic-hardness regionof 30.3 GPa. The average fracture toughness was measured as 4.1MPa m1/2.Additionally, We also measured the hardness and elastic properties ofpolycrystalline {\beta}-B and PcBN for comparison. The hardness and elasticproperties for polycrystalline {\gamma}-B was found to be very close to that ofPcBN. Our results suggest that the polycrystalline {\gamma}-B could be asuperhard polycrystalline material for industrial applications.
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