Effect of Ti-containing complex inclusions on the microstructure and mechanical properties of medium carbon non-quenched and tempered steel;

The results show that the presence of larger amount of the complex inclusion containing elements of O,Mn,Fe,Mg,Al,S and Ca in the stuff which was smelted results in the crack of the cold forging steel during the cold heading process.

The inclusions in steel was analyzed by using SEM, The reason of improving machinability was discussed It shows that the spindly MnS and its compound type inclusions with nucleus of Al2O3, SiO2 may improve machinability of materials.

MnS - bearing compound type inclusions are easily ob-tained with certain oxygen co.

The effect of the oxygen content before solidification on the type of the precipitated ultra-fine complex oxide in Mn and Ti alloyed steel has been studied by means of thermodynamic calculation and experiment.

Two Ti-complexes were bound into the channel of MCM-48 successfully.

Compared with unbubbling,during the argon bottom bubbling technology of Cr20Ni35 alloy production,when the argon flow is 3L/min,the element O contents dopped 36%and 23%,the total amount of non-metallic inclusions reduced 24% and18%.