| Now the Chinese pen industry is developing rapidly, and producer has ranked top lines in the world. However most free cutting stainless steel materials used in Ball Pen dependence on imports. There are big gap in mechanical properties of the material and high-speed cutting performance between Chinese materials and imported. Thus, the traditional Chinese pen-materials can not meet the needs of development of pen industry.Our task force make a full investigation of technology and equipment, then developed an international advanced level of S-Pb compound test ferrite cutting stainless steel. In order to test the performance of a comprehensive assessment of test steel, experiment method and simulation test method were used to compare SF20 T cutting stainless steel with test cutting stainless steel. The achieved results are as follows:1. To study the chemical composition and SEM of test SF20 T steel and cutting stainless steel. The results show that: the chemical composition of SF20 T cutting stainless steel and test STF20 T are similar, both are sulfur- Pb compound ferritic stainless steel. Manganese(Mn) and chrome(Cr) element content of test steel is lower slightly, molybdenum(Mo) and lead(Pb) increased slightly. By means of scanning electron microscopy back scatter technology, Pb appeared individual in the matrix, and most present in the boundary in the MnS inclusions to form complex inclusions. MnS inclusions in the cross-section have a rarely ellipsoidal or spindle-shaped, and formed intermittent chain in the longitudinal direction. MnS inclusions in Test steel is more even compared with SF20 T, and more conducive to high-speed machining.2. Comparative analysis of the mechanical properties of test steel and SF20 T cutting stainless steel. Based on test steel, the results show that: tensile strength σ_b=752MPa, yield strength σ2.0 =612MPa, elongation δ =3.0%, reduction rate ψ =48%.Based on SF20 T cutting stainless steel, the results show that: tensile strength σ_b=803MPa, yield strength σ2.0 =638MPa, elongation δ =3.5%, reduction rate ψ =58.3%.The value of toughness and ductility of test cutting stainless steel is more larger than SF20 T cutting stainless steel. Axis dimples appeared in section center and cut dimples presented in edge which were belong to ductile fracture of test cutting stainless steel and SF20 T cutting stainless, but SF20 T cutting stainless has larger result in depth and size of dimples, at the same time, better toughness and ductility were proved go with experimental data.3. Comparative analysis the hardness and wear resistance of test cutting stainless steel and SF20 T cutting stainless steel. It is found that: those two materials whose hardness is similar, but uniformity of ST20 T is better. The conclusion from the test data,the nick depth of test cutting stainless steel is 0.28 mm,and the depth of SF20 T cutting stainless steel is 0.38 mm.SF20T cutting stainless steel have better wear resistance than test cutting stainless steel.4. Through the FEM software DEFORM-3D to simulate the process of high-speed drilling, and study whose chip and wear value of tool. At the stable stage of drilling, The drilling force,drilling temperature and tool wear values of test cutting stainless steel are slightly less than SF20 T cutting stainless steel. Drilling through experimental comparison test drilling steel swarf cutting smaller than the SF20 T and difficult to stick stainless steel knives, steel processing machining tool wear test showed a smaller test high-speed drilling of steel and better performance with the simulation results coincide.By controlling experiment parameter to explore the variation of drilling force, drilling temperature, tool wear value of two materials. |
PDF Full Text Request