Study On The Preparation And Tribological Performance Of Multi-Dimensional Nanomaterial Reinforced Light-Curing Resins

Polymer materials are self-lubricating,wear-resistant,corrosion-resistant,light-mass,and low cost,and are used as solid lubricating materials in the lubrication of machinery and equipment.Compared to traditional forming methods for polymers,3D printing does not require moulds and is characterized by high designability,material utilization,and forming accuracy.Photosensitive acrylic resin(PAR)is a light-curing material commonly used for the 3D printing of self-lubricating polymers.However,the low mechanical properties of pure acrylic resins limit their use as 3D printing self-lubricating materials in a wide range of industrial applications.To overcome these drawbacks,polymer-based composites are prepared by adding a nanomaterial reinforcing phase to the polymer.Depending on the nanomaterial structure,the polymer composites are made to have different tribological,mechanical,and thermal properties.For this reason,this paper uses PAR as the matrix material and zirconia(ZrO2)and boron nitride nanosheets(BNNS)as the reinforcing phases.The multi-dimensional nanoreinforcements and their PAR-based composites were prepared by lanthanum salt modifiers.The effectiveness of single-dimensional and multi-dimensional nano-reinforcement on PAR enhancement was compared.The tribological behavior of the PAR-based composites under dry friction conditions was investigated,the wear mechanism was analyzed and a friction model was built.Details are as follows:(1)The mechanism of the effect of PAR light-curing forming process parameters on its comprehensive properties was investigated.A three-factor mixed orthogonal table was designed by the orthogonal experiment,i.e.,the three key process parameters of the thickness of each printed layer(P),heat treatment(H),and UV treatment(U).The priority of the three process parameters in influencing tribological properties was investigated based on the grey correlation theory.The "wear efficiency" was defined to evaluate the wear resistance and printing efficiency of the samples.The results show that the order of priority is P,U,and H.The tribological and mechanical properties of PAR decreases with increasing layer thickness.The optimum value of the comprehensive material properties was reached when the printed layer thickness was 30 μm.The UV treatment increases the cross-linking of molecules between the PAR layers.The heat treatment reduces the residual stresses generated during the printing process and the residual stresses decrease with increasing heat treatment temperature up to 80℃,which in turn increases the mechanical properties with increasing heat treatment temperature.(2)The mechanism of the effect of photocurable forming of PAR matrix composites on their tribological properties was investigated.Carboxylated zirconium oxide(mZrO2)and hydroxylated boron nitride(mBNNS)were obtained by chemical modification,and multidimensional reinforcements(mBNNS-La-mZrO2)were obtained by lanthanum ion modification.XPS,Raman,and FTIR were used to characterize the nano-modification mechanism.Tribological tests and SEM analysis were carried out to investigate the tribological mechanism.The results show that the mBNNS-La-mZrO2/PAR composite has the best comprehensive properties,with a 20.62%reduction in friction coefficient and a 65.75%reduction in wear rate.The lanthanum ion modification treatment improved the dispersion stability of the mBNNS-La-mZrO2/PAR composites.(3)The mechanism of the effect of photocurable forming of PAR matrix composites on their thermal and mechanical properties was investigated.The temperature resistance of the composites was analyzed by TGA.The mechanical properties of the PAR matrix composites were evaluated by tensile and flexural tests and the fracture mechanism was investigated by microscopic morphological analysis of the damaged fracture surfaces.The results show that the mBNNS-La-mZrO2/PAR composites have the best comprehensive properties.Among them,the thermal properties were improved by about 13.27%,the tensile strength and tensile modulus by about 229.00%and 42.41%,respectively,and the flexural strength and flexural modulus by about 84.64%and 84.82%,respectively.In this paper,multi-dimensional nano-reinforcements were prepared and the nanomodification mechanism was characterized by XPS,Raman,and FTIR.The friction wear and the thermal and mechanical performance of the multi-dimensional nano-reinforced PAR-based composites were investigated.A self-lubricating composite with good overall performance was obtained which provides experimental data and theoretical basis for the use in friction and wear reduction of mechanical rotary components.