Preparation And Properties Of TiC Reinforced 316L Stainless Steel By Metal Powder Injection Molding

In this paper,the metal surface modifier PEG-EP resin(PEG-EP)was synthesized from polyethylene glycol 4000(PEG-4000)and epoxy resin E51.The best reaction conditions of PEG-EP resin were explored by using epoxy value and FT-IR.The crystallization performance of PEG-EP on POM was analyzed by using differential scanning calorimetry(DSC),universal testing machine and rotational rheometer The 316L stainless steel powder(316L)was treated by the synthetic metal surface modifier PEG-EP.the preparation and sintering of special material(feed)for injection molding of 316L stainless steel powder by PEG-EP were investigated by infrared analysis,contact angle measuring instrument,plate rheometer,mechanical properties,scanning electron microscope(SEM),metallographic microscope,x-ray diffraction(XRD),characterization of residual carbon content and hardness On the basis of PEG-EP surface modification of 316L stainless steel powder,titanium carbide(TiC)powder with different particle size and content was added into 316L powder,and its influence on the properties of TiC reinforced 316L stainless steel prepared by metal powder injection molding was studied by SEM,XRD,metallographic microscope,hardness,density,mechanical properties,friction and wear test.The main research contents and results are as follows:1.PEG-EP was successfully synthesized by PEG4000 and E51.the best conditions for synthesizing PEG-EP were reaction temperature130 ^oC,catalyst KPS content 0.75%and reaction time 3 h.The research on the non-isothermal crystallization kinetics of PEG-EP/POM blends shows that PEG-EP is intertwined with POM molecular chains,and PEG-EP will prevent POM molecular chains from rearranging and stacking neatly during POM crystallization,thus inhibiting POM crystallization.When the content of PEG-EP is 40%,the elongation at break and impact strength of POM are increased by 28.25%and 3.7KJ/m²,respectively,and the toughness and flow properties of POM are also improved.2.PEG-EP successfully coated on the surface of 316L powder,and improved the interfacial compatibility between 316L stainless steel powder and polyoxymethylene,and improved the fluidity of feed,the mechanical properties of green body and the mechanical properties and hardness of sintered samples.At the same time,PEG-EP is not completely decomposed during sintering,resulting in residual carbon,which becomes external crystal nucleus during sintering,inhibiting the growth of dendrites and refining grains.When PEG-EP content is0.662%and powder loading is 63 vol%,the tensile strength,elongation at break and bending strength of 316L injection green body are 10.57MPa,8.38%and 21.24 N?(mm²)^-1,respectively.The grain size of sintered sample is 50.8?m,and the maximum tensile strength and Vickers hardness are 689 MPa and 151 HV.3.TiC was successfully introduced into 316L stainless steel matrix,adding TiC can refine the grain size of 316L stainless steel.After adding 3%of 1?m TiC,the grain size of TiC/316L powder injection molding sintered sample decreased from 50.8?m of 316L modified by PEG-EP surface to 23.6?m;The density and hardness also increased from 7.57 g/cm³ to 7.84 g/cm³ and 151 HV to 301 HV;respectively.The stress increased from 689 MPa to 792 MPa,and the yield strength increased from 221 MPa to 339 MPa;The friction coefficient and wear cross-sectional area decreased from 0.853 to 0.761,and 22054.90?m²to 9428.38?m²,and the comprehensive properties of TiC/316L powder injection molding sintered samples were improved.At the same time,TiC with particle size of 0.1?m will agglomerate and bond with 316L matrix interface weakly,resulting in cracks and defects,resulting in lower comprehensive properties than TiC with particle size of 1?m at the same content.