Effect Of Pressure On Density, Porosity And Flexural Strength During Cold Isostatic Press Of Alumina-Ysz-Chromia Cutting Tool

Porous titanium compacts were fabricated by powder metallurgy using cold isostatic press with and without pore forming agents. Their microstructure and mechanical properties were investigated in this study. These alloy powders were sintered under 1300°C in vacuum of 10-3 Pa for 2h, followed by furnace cooling. Young’s modulus of sintered Ti could equal that of human’s dense bones. It was found that the strength of porous Ti enhanced by increasing the pressure or decreasing the amounts of pore forming agents. We prepared a porous pure Ti with 30wt.% NH4HCO3 as pore forming agents whose modulus was near to the human cortical bone, as compared in the range from 10 to 30GPa of Young’s modulus for human bone.

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Mechanical Properties and Microstructure of TiN-TiB2 Composite Ceramic Cutting Tool Material

Materials Science Forum ◽

10.4028/www.scientific.net/msf.800-801.430 ◽

2014 ◽

Vol 800-801 ◽

pp. 430-434 ◽

Cited By ~ 3

Author(s):

Li Mei Wang ◽

Han Lian Liu ◽

Chuan Zhen Huang ◽

Xue Fei Liu ◽

Bin Zou

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Flexural Strength ◽

Cutting Tool ◽

Sintering Temperature ◽

Tool Material ◽

Composite Ceramic ◽

Ceramic Cutting Tool

TiN-TiB2 composite ceramic cutting tool material was prepared with hot pressed sintering in vacuum. The effects of sintering temperature and Ni additive on mechanical properties and microstructure were investigated. It is shown in the results that the fracture toughness decreases consistently with an increase of the sintering temperature, while the flexural strength of the TiN-TiB2 composite increases firstly and then decreases with an increase of the sintering temperature. The flexural strength of the TiN-TiB2 composite increases firstly and then decreases with an increase of the Ni additive, while the fracture toughness increases consistently with an increase of the Ni additive. The optimum comprehensive mechanical properties were obtained with the additive of 5wt.% Ni while sintered at 1650°C; the corresponding values were as follows: flexural strength of 966.1±190MPa, fracture toughness of 6.36± 0.9MPa·m1/2 and hardness of 18.8±2.4GPa respectively.

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The Chatterbox: A Device for Hearing Chatter as Sections are Cut

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072241 ◽

1973 ◽

Vol 31 ◽

pp. 360-361

Author(s):

C. W. McCutchen ◽

Lois W. Tice

Keyword(s):

Machine Tools ◽

Cutting Tool ◽

Guerilla Warfare ◽

History Of ◽

Chatter Marks

Ultramicrotomists live in a state of guerilla warfare with chatter. This situation is likely to be permanent. We can infer this from the history of machine tools. If set the wrong way for the particular combination of cutting tool and material, most if not all machine tools will chatter.In more than 100 years since machine tools became common, no one has evolved a practical recipe that guarantees avoiding chatter. Rather than follow some single very conservative rule to avoid chatter in all cases, machinists detect it when it happens, and change conditions until it stops. This is possible because they have no trouble telling when their cutting tool is chattering. They can see chatter marks, and they can also hear a sometimes deafening noise.

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