Abstract：Berkovich nanoindentation experiments on a fused silica sample with different tilt angles were carried out. The indentation results show that the tilt of the sample affects the shape of the loading curves. The maximum indentation depth, residual depth and contact depth gradually decrease with the increase of the tilt angle of the specimen at the same indentation load, but the unloading curves are not affected, and they remain parallel to each other, the fitting parameter m of the unloading curves and the value of contact stiffness remain constant regardless of the inclination of the sample. In addition, it is found that the sample tilt will lead to smaller indentation projected contact area, which will make the hardness and elastic modulus larger.
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2019, Vol. 40 
