4 results about "Contact depth" patented technology

The application discloses a pure titanium nanometer scale oxide layer nanometer probe precise detection method, which comprises the following steps: S1, preparing a titanium sample to be measured, and pretreating the titanium sample to be measured to make the surface of the titanium sample to be measured smooth; S2, selecting multiple test points on the surface of the titanium sample to be measured and marking the test points, using a pressure head of a nano indentation instrument to make an indentation on the marked test points, and obtaining surface indentation data; S3, selecting multiple test points on the cross section of the titanium sample to be measured and marking the test points, using the pressure head of the nano indentation instrument to make an indentation on the marked test points, and obtaining cross section indentation data; S4, summing up the maximum contact depth in the surface indentation data of each test point and taking an average value, and marking the average value as a; summing up the maximum contact depth in the cross section indentation data of each test point and taking an average value, and marking the average value as b; and taking a difference between a and b to obtain an influence value of the oxide layer on the titanium surface. The application can simply and quickly evaluate the influence of the oxide layer on the titanium surface by using the nano indentation method.

The application discloses a vibration type air grinder polishing material removal rate prediction method, comprising the following steps: S1, sequentially extracting track points in a polishing track, and taking a currently extracted track point as a current initial contact point; S2, calculating a maximum contact depth h0 corresponding to a constant polishing force F at the current initial contact point, and then calculating the size of a current polishing area; and S3, calculating a material removal rate under the current constant polishing force F and the polishing area, wherein the removal rate represents a removal thickness. According to the method, the maximum contact depth of a polishing disc and a workpiece to be polished in a polishing process is used to represent polishing force and material removal rate, the polishing force size is calculated by using contact area equivalence, and the method is suitable for polishing of vibration polishing discs with different shapes.

The invention discloses a contact force planning method and device for deterministic force control grinding and polishing, and belongs to the technical field of contact force planning. The method comprises the following steps: preprocessing point cloud data to obtain workpiece point cloud data; flexible grinding contact modeling is carried out based on the workpiece point cloud data, and a contact model between the tool pressing amount and the contact depth, the contact point index set and the contact pressure is obtained; establishing a material removal model based on the contact model and a convolutional material removal principle, and obtaining a least square form of the material removal model; solving the least square form to obtain a tool pressing amount; the contact force is calculated based on the tool pressing amount. According to the method, the tool pressing amount is used for acting as the contact force, the contact force facing deterministic grinding is obtained by optimizing the tool pressing amount, the optimization method supports multiple numerical solution strategies, the planned contact force can implement different contact forces at different tool location points, the machining allowance is matched with the material removal depth, and the machining precision is improved. And the accuracy of contact force planning is improved.

The invention relates to a method and a system for measuring the interface bonding strength of a gallium nitride power device. The method comprises the following steps: dividing a first test area and a second test area on a gallium nitride sample film; performing a nano indentation test on the gallium nitride sample in the range of the first test area, calculating to obtain elastic modulus data, hardness data and contact depth data under different indentation depths, and obtaining a residual diameter value of an indentation; performing linear fitting on the data, and calibrating to obtain an elastic recovery dimensionless coefficient of the gallium nitride sample; performing a nanometer cut-in test in the range of the second test area of the gallium nitride sample to obtain a critical load value and a residual scratch width value when the interface fails; the residual scratch width value is corrected into a real contact width value during loading; calculating the average thermal stress of the interface; and inputting the real contact width value and the interface average thermal stress into a preset interface stress calculation model to obtain an interface bonding strength detection result of the gallium nitride sample.