On-site nondestructive testing device for hardness of metal sheet

The invention discloses an on-site nondestructive testing device for the hardness of a metal sheet. The on-site nondestructive testing device comprises a detection supporting column body, a pressing plate sliding block, an adjusting mechanism and a Leeb hardness detection head; the upper end face of the detection supporting column body is an arc surface protruding upwards to form a supporting arcsurface; the pressing plate sliding block is connected with the detection supporting column body through an adjusting mechanism, the pressing plate sliding block comprises a clamping part, the clamping part is located over the supporting arc surface, and a mounting hole is formed in the position, corresponding to the supporting arc surface, of the clamping part in an up-down penetrating mode; andthe Leeb hardness detection head is downwards arranged at the mounting hole. According to the on-site nondestructive testing device provided by the invention, the back surface of a stress point is impacted by the impact head o