Fracture toughness tester and fracture toughness test method
細井厚志 (Inventor), 川田宏之 (Inventor), 原田和樹 (Inventor) & Jespersen, K. M. (Inventor), 27 May 2021, IPC No. G01N 3/ 08 A I, Patent No. JP2021081191, 14 Nov 2019, Priority date 14 Nov 2019, Priority No. JP20190205932