Tribological Properties And Preparation Of A Series Of Ti-Al Inter-metallic Films

Ti-Al inter-metallic compounds have good physical and chemical properties under high temperature and good mechanical properties,lower prices,low density.As a structural material,it has broad application prospects in the aviation,aerospace,automotive,and other fields.However,due to the brittle property,it is difficult to be made into products with complex shapes,but films can be deposited on the complex surface.In this paper, depositing Ti-Al inter-metallic compounds film on stainless steel,copper and silicon surface by microwave plasma RF magnetron sputtering equipment.Then,we discussed the phase composition,morphology and friction performance of the films by X-ray diffraction (XRD),scanning electron microscopy(SEM)with a spectrometer(EDS),and UMT-2 model tribology testing machine experimental equipment.Mainly by the following conclusions:1.The content of Al in Ti-Al inter-metallic compounds film that deposited on the stainless steel substrate by the way of Titanium aluminum dual-target RF magnetron sputtering is different(the distance between substrate and target is different,so the content of Al is different).Detection by XRD,when the nitrogen is absent,the film is made up of TiAl,TiAl₃,Al₂O₃ and TiO₂ phase.When the nitrogen is access,the major structure in films is the(Ti,Al)N phase of(111)and(200)orientation;and with the increase of Al content and N₂/Ar ratio,(111)orientation of(Ti,Al)N phase gradually weakened,(200) orientation has been enhanced.Among the range of 600～750℃heat temperature,the temperature has little effect on the phase of films.2.The quality of the films deposited by Titanium aluminum dual-target RF magnetron relate to the substance material.The deposition on the silicon and copper is not very satisfactory.By analyzing the EDS patterns can be found that Ti and Al components on the copper and silicon are few,and we could not find any Ti-Al inter-metallic compounds by XRD patterns also. 3.When no nitrogen in the circumstances,from the SEM images of thin films on different substance can be seen that the thin films on the stainless steel has high density,the organizations of the thin films surface is uniform;atomic arrangement in the thin film on copper surface is different in the level and loose;the films on silicon is thin,we can't see their morphology.4.When there is Nitrogen in the circumstances,thin film deposited on stainless steel is homogeneous,can clearly see its morphology.With the increased of nitrogen,firstly,grain morphology from larger Flake profile become into the small cylindrical profile,and then into the larger irregular of columnar shape.After 30 min of friction testing,a lot of wear debris on both sides of(Ti,Al)N thin films worn trace,and the abrasive wear is clear.In the Worn trace,there is some small trench with a small flake.It is the result of fatigue wear mechanisms and abrasive wear mechanism.5.The friction coefficient of the Ti-Al inter-metallic compounds films with different of Ti/Al components deposited in this study is low,and the wear resistance is excellent.In the circumstances without Nitrogen,when the content of aluminum is high,the life of films is short.About after 15 min to 20 min of friction testing,the film will be worn out.When Ti/Al≈1,the film has the lowest friction coefficient,can be reached about 0.05.When there is Nitrogen in the circumstances,the films with aluminum content about 46%has the lowest friction coefficient,can be reached about 0.02.