In-situ indentation mechanical testing device based on tensile compression and fatigue combined load mode

The invention relates to an in-situ indentation mechanical testing device based on tensile compression and fatigue combined load mode, and belongs to the field of precise testing instruments. The device is mainly composed of a precise driving unit, a tensile compression and fatigue combined load unit, an indentation load unit, a precise sensing and detecting unit, wherein the precise driving unit can realize quasi-static load; the tensile compression and fatigue combined load unit enables the center of a testing piece to be kept unchanged basically; with combination of a high-resolution imaging system, observation of in-situ mechanical performances of a material can be carried out. A fatigue module is loaded on a tensile compression module, so that fatigue performance of the material can be tested by adopting the precise piezoelectric driving technology. The indentation load unit is arranged right above the testing piece and is pressed in the testing piece vertically, a lead screw stepping motor drives an indentation flexible hinge to feed linearly, and an indentation piezoelectric stack pressed in the testing piece drives precise indentation, so that cross-scale in-situ indentation mechanical test can be carried out. The device has the advantages of compact structure, small size, rapid response, high precision, low cost and the like.