| With the rapid development of intelligent manufacturing and precision machining,higher requirements are put forward to the temperature measurement of machining tools.At present,most of the temperature sensors are discrete devices,without protection function,can not be installed in the harsh working environment of friction,oxidation and corrosion,and the sensor is far from the working surface,can not accurately reflect the real-time temperature state of tools and mechanical parts.This paper intends to develop the integrated technology of embedded thin film temperature sensor for intelligent manufacturing,to overcome the key technical problems in the design and manufacturing of the integrated structure and function thin film sensor,and to meet the needs of intelligent manufacturing.The main research results are as follows:1.Preparation and structural properties of AlN/Al2O3 composite insulating film.In this paper,AlN insulating film was deposited by DC magnetron sputtering(dcMS)with cemented carbide as substrate.By changing the pretreatment parameters of anode layer ion source etching current,Ar pressure and etching time,etching and cleaning the substrate is used to improve the bonding force between AlN film and substrate.Appropriate reduction of Ar pressure can also improve the etching effect and increase the roughness of the matrix.Secondly,the effects of N2 partial pressure on the phase structure,morphology and insulation properties of AlN thin films were studied.When the deposition pressure was controlled as 0.4 Pa,when the N2 partial pressure was 40%,the atomic ratio of Alto N in AlN thin films was in accordance with the stoichiometric ratio.At this time,AlN thin films had the densest structure,the best insulation,and the resistivity could reach 7.3×1011?·cm.In this paper,atomic layer deposition(ALD)technology is used to deposit Al2O3 film on the surface of AlN film to fill the microholes of AlN film.DCMS-AlN/ALD-Al2O3 composite film can block the conduction between W atom and conductive matrix and provide excellent insulation performance,especially at high temperature.2.Study on the structure and thermal resistance properties of W thermal resistance films prepared by magnetron sputtering deposition.The effects of deposition parameters including bias,air pressure and temperature on the microstructure and thermal resistance of W films were studied by using DC magnetron sputtering technique.By changing the microstructure of W films,the influence of thermal resistance on the sensing films was studied.It was found that the W films with larger grain size and higher compact structure had better thermal resistance.The effect of size and shape on the structure and thermal resistance of W films was studied.The results show that after several thermal resistance tests,recovery and recrystallization of the W films deposited by the optimized process occur,and fine grains appear on the surface of the films.3.Preparation of W-base alloy thermal resistance thin films by elemental doping and its structure and properties.The WTi alloy thin films with 0?23 at.%Ti component content were deposited by magnetron sputtering,and Ti was dissolved in W lattice to form a single phase solid solution.When the Ti content is 6.8 at.%,the TCR of the alloy film reaches the maximum value of 19.5×10-4 K-1,which is 3.6 times higher than that of the pure W film(TCRW=5.43×10-4 K-1).The TCR of the alloy film has a good thermal-resistance correlation display performance.After annealing at 500?for 30 min,the grain size of WTi alloy film(6.8 at.%Ti)increases,a few pores appear,and the density of the film decreases.The TCR decreases from 19.5×10-4 K-1 to 14×10-4 K-1.When the annealing time is increased to 60 min,the structure and properties of WTi alloy films remain basically unchanged.After annealing treatment for 30 min,the W film shows excellent thermal resistance test stability,and its TCR is basically consistent after cyclic thermal loading,which has a promising application prospect for temperature measurement of tools and dies. |
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