Preparation And Tribological Properties Of High-Strength And Titanium Material By Using Rice Husk As SiO₂ And C Source

The annual output of rice husks is huge,and these rice husks are often not used properly,making rice husks have a greater impact on the environment.Rice husk is rich in SiO2,and Si is one of the important elements of high-performance titanium materials.Therefore,waste rice husks are fully used to prepare high-strength titanium alloys with SiO2 and C sources,and their lattice constants after distortion Perform fitting calculations.In this paper,the rice husk was pickled with citric acid solution first,and the pickled rice husk was heated in a tube furnace to prepare rice husk SiO2 powder and SiO2/C powder.The SiO2/Ti material and the corresponding ratio of Ti-SiO2-C composite material were prepared by hot pressing and sintering.The influence of SiO2 content on the lattice distortion of titanium material and the effect of SiO2 content on SiO2/Ti material and Ti-SiO2-C composite material were studied.The influence of the mechanical properties of materials and the influence of SiO2 content on the friction and wear properties of the prepared Ti materials are discussed.The friction and wear mechanism of the materials is discussed.The main conclusions obtained in this paper are as follows:(1)XRD phase analysis shows that the characteristic peaks of SiO2/Ti materials are all characteristic peaks of α-Ti,which are shifted to the right compared with pure titanium.In the XRD pattern of the Ti-SiO2-C composite material,it can be found that in addition to the characteristic peak of a-Ti,the characteristic peak of TiC appears,indicating that a new phase is formed.(2)Obvious a-Ti phase can be found in the metallographic photos of SiO2/Ti material and scanning electron microscope images,and with the increase of the composition content,the acicular a-Ti phase inside the crystal grains and the crystal lattice gradually decreases.Obvious TiC phases can be found in the metallographic photos and scanning electron micrographs of TiSiO2-C composite materials,which are granular and distributed inside the crystal grains.(3)In this paper,the lattice constants(a value and c value)of the SiO2/Ti alloy with different contents are calculated by the interplanar spacing formula and the Bragg diffraction equation,and the calculation results are fitted.The fitting result is a[SiO2]wt.%=2.9538-0.0048.SiO2%,C[SiO2]wt.%=4.6952-0.0058·SiO2%,indicating that the combination of silicon and oxygen causes negative distortion on the titanium lattice,but the effect is not significant.(4)The density of the alloy composite sample and the pure titanium sample sintered under the set sintering process are both about 99.7%,and both reach densification.The Vickers hardness of the pure titanium sample is 262HV,and the hardness of the other component materials is greater than that of the pure titanium sample.The hardness of Ti-SiO2-C composite material added with SiO2/C powder is improved on the basis of SiO2/Ti material.(5)Compared with pure titanium samples,the prepared alloy and composite material samples have greatly improved wear resistance.As the content of rice husk decomposition products(SiO2)increases,the friction coefficient and wear rate show a decrease status.Abrasive wear is the main wear mechanism of Ti materials and composite materials.The law of the prepared Ti material and composite material samples under different load and speed conditions is that when the load and speed increase,the friction coefficient does not increase but decreases,and the wear rate gradually rises.The wear mechanism is based on abrasive wear.Mainly,contains a small amount of adhesive wear.