Ultra-low temperature impact testing machine is a kind of testing equipment. Test for determination of notch sensitivity (toughness) of metallic materials. The impact testing machine uses liquid nitrogen refrigeration, the lowest temperature can reach -196 ° C (-196 ° C is a special requirement), especially suitable for determining the impact resistance of metal materials at very low temperatures. It is an important test means for detecting materials and researching and developing new materials in metallurgy, machinery manufacturing, scientific research and testing units.