The scratch behaviors of two high speed steels （HSS） for hot rolls were studied by a Micro-combi Tester, and the emphasis was placed on researching the relations between the microstructure and the scratch resistance...The scratch behaviors of two high speed steels （HSS） for hot rolls were studied by a Micro-combi Tester, and the emphasis was placed on researching the relations between the microstructure and the scratch resistance property of different HSS. The experimental results indicate that during the scratch process, the carbides are embedded into the matrix, the penetration depth of different HSS is closely related with the matrix hardness, i.e., the higher the matrix hardness, the better the scratch resistance property; and in the matrix, the fine, dispersive carbides are beneficial to form steady friction between the indenter and the scratched materials, but the coarser carbides are easier to fall into pieces.展开更多
By combination of DC reactive magnetron sputter i ng with multiple arcplating, the alternating C 3 N 4 /TiN compo und film is deposited onto HSS. The core level binding energy and the contents o f carbon and n...By combination of DC reactive magnetron sputter i ng with multiple arcplating, the alternating C 3 N 4 /TiN compo und film is deposited onto HSS. The core level binding energy and the contents o f carbon and nitrogen are characterized by X\|ray photoelectron spectrum. X\|ray diffraction(XRD) shows that compound thin film contains hard crystalline phases of α \|C 3 N 4 and β \|C 3 N 4 . The Knoop microhardne ss in the load range of 50.5\|54.1 GPa is measured. According to acoustic emissi on scratch test, the critical load values for the coatings on HSS substrates are in the range of 40\|80 N. The metal coated with C 3 N 4 /TiN compound f ilms has a great improvement in the resistance against corrosion. Many tests sho w that such a coating has a very high wearability. Compared with the uncoated an d TiN coated tools, the C 3 N 4 /TiN coated tools have a much longer cut ting life.展开更多
In this paper, ASP2030 （A30） high speed steel （HSS） was produced by spray forming and the microstructure was studied by optical microscopy （OM）, scanning electron microscopy （SEM）, transmission elec- tron micr...In this paper, ASP2030 （A30） high speed steel （HSS） was produced by spray forming and the microstructure was studied by optical microscopy （OM）, scanning electron microscopy （SEM）, transmission elec- tron microscopy （TEM）, electron probe microanalysis （EPMA） and X-ray diffraction （XRD）. The spray formed A30 （SF A30） steel exhibited a very uniform and fine microstructure consisting of martensite, retained austenite and uniformly distributed network carbides. Microstructure refining can be explained in terms of the rapid solidification of spray forming. M2C, MC and M6C type carbides were found in the as-sprayed A30 HSS by XRD and TEM. A uniform distribution of carbides was obtained after forging and annealing. The microstructure properties of SF A30 steel indicate that spray forming can be considered as a cost-effective route for the production of A30 steels and other highly alloyed steels.展开更多
文摘The scratch behaviors of two high speed steels （HSS） for hot rolls were studied by a Micro-combi Tester, and the emphasis was placed on researching the relations between the microstructure and the scratch resistance property of different HSS. The experimental results indicate that during the scratch process, the carbides are embedded into the matrix, the penetration depth of different HSS is closely related with the matrix hardness, i.e., the higher the matrix hardness, the better the scratch resistance property; and in the matrix, the fine, dispersive carbides are beneficial to form steady friction between the indenter and the scratched materials, but the coarser carbides are easier to fall into pieces.
文摘By combination of DC reactive magnetron sputter i ng with multiple arcplating, the alternating C 3 N 4 /TiN compo und film is deposited onto HSS. The core level binding energy and the contents o f carbon and nitrogen are characterized by X\|ray photoelectron spectrum. X\|ray diffraction(XRD) shows that compound thin film contains hard crystalline phases of α \|C 3 N 4 and β \|C 3 N 4 . The Knoop microhardne ss in the load range of 50.5\|54.1 GPa is measured. According to acoustic emissi on scratch test, the critical load values for the coatings on HSS substrates are in the range of 40\|80 N. The metal coated with C 3 N 4 /TiN compound f ilms has a great improvement in the resistance against corrosion. Many tests sho w that such a coating has a very high wearability. Compared with the uncoated an d TiN coated tools, the C 3 N 4 /TiN coated tools have a much longer cut ting life.
文摘In this paper, ASP2030 （A30） high speed steel （HSS） was produced by spray forming and the microstructure was studied by optical microscopy （OM）, scanning electron microscopy （SEM）, transmission elec- tron microscopy （TEM）, electron probe microanalysis （EPMA） and X-ray diffraction （XRD）. The spray formed A30 （SF A30） steel exhibited a very uniform and fine microstructure consisting of martensite, retained austenite and uniformly distributed network carbides. Microstructure refining can be explained in terms of the rapid solidification of spray forming. M2C, MC and M6C type carbides were found in the as-sprayed A30 HSS by XRD and TEM. A uniform distribution of carbides was obtained after forging and annealing. The microstructure properties of SF A30 steel indicate that spray forming can be considered as a cost-effective route for the production of A30 steels and other highly alloyed steels.
