Study On The Microstructure And Performance Of Nmag100Non Magnetism Steel

In this thesis, the hot deformation behavior and evolution of the microstructure of Nmag100Non Magnetism Steel have been studied with the aids of optical microscope on high temperature thermal simulator testing. Microstructures and properties of Nmag100Non Magnetism Steel at different states including hot、 homogenization treatment and thermally aged have been analyzed and tested. Conclusions can be drawn as follows:(1) The influences of hot deformation parameters on high temperature deformation resistance of Nmag100Non Magnetism Steel have been studied. The results showed that deformation resistance of Nmag100Non Magnetism Steel increases with decreasing deformation temperature and increasing of strain rate. The effects of strain on deformation resistance will have a complex change depending on recovery process such as dynamic recovery and dynamic recrystallization caused by changes of deformation temperature and strain rate.(2) The model of deformation resistance of Nmag100Non Magnetism Steel has been established using Origin software through the experimental date accessed by thermal simulation experiment, and it has higher fitting precision.(3) The microstructure of Nmag100Non Magnetism Steel is austenite, hot-rolling Nmag100Non Magnetism Steel shows a yield strength and a ultimate strength of550MPa and713MPa respectively, and a homogeneous elongation of44%in the normal temperature and it shows a yield strength and a ultimate strength of580MPa and890MPa respectively, and a homogeneous elongation of62%in the low temperature.The microstructure of Nmag100Non Magnetism Steel after solution treatment was austenite too, and it shows the highest strong plastic product,43.882GPa%, at1030℃of solid solution temperature. The microstructure of600℃aged treated Nmag100Non Magnetism Steel consists of austenite almost. The yield strength was346MPa, ultimate strength was612MPa, homogeneous elongation was68%. It shows the highest strong plastic product,41.616GPa%. Nmag100Non Magnetism Steel has no distinctly difference of mechanical properties after thermal ageing which was thermal aged at600℃. Experimental results show that the fracture toughness for steel fracture nest fracture, and shows good ductile fracture characteristics.(4) In the whole shock temperature range, solid solution states are more8J than the hot rolling state. As the temperature is reduced, impact absorption power decreases, but a gentle slope curve, even in196℃still has high impact toughness. The fracture was SEM images, belongs to the typical ductile fracture. It also confirmed that the experiment has high impact energy of steel absorb ability as well as the structure in the low temperature of a higher toughness.(5) The hot-rolling Nmag100Non Magnetism Steel shows magnetic permeability of1.0043H/m in the normal temperature and it shows1.0039H/m after solution treatment.