An integrated approach to the characterization of powder metallurgy components performance during green machining

Machinability of Green Powder Metallurgy Components: Part I. Characterization of the Influence of Tool Wear

“…The advantages of this approach are impressive: the cutting forces and the temperature in the cutting zone are kept to a minimum while allowing an increase in productivity. [11] On the other hand, these benefits could easily be offset by the much lower strength of green parts, which can lead to a poor surface finish, broken edge during machining, or even broken parts during clamping. [12] However, advancements in binder/ lubricants and in compaction technologies have led to the development of high green strength components that enable green machining.…”

“…High-quality features, such as holes and grooves, have been successfully machined in green compacts produced using warm compaction or the binder technologies. [11,[13][14][15][16][17][18][19][20] In the case of the latter, conventional lubricants are replaced by polymeric-based systems that significantly strengthen the parts. In some cases, these powder systems can be made even more efficient by performing a curing treatment in air at relatively low temperatures (175°C to 200°C) for one 1 hour.…”

Machinability of Green Powder Metallurgy Components: Part II. Sintered Properties of Components Machined in Green State

“…[11] Also, it is believed that the feed rate must be kept to a value of 0.0254 mm/r (or even lower), for preventing the pullout of particles near the edges and for optimizing the surface finish. [11][12][13][14][15][16] However, based on the conclusions presented in Part I, this statement is only partly true. A feed rate of 0.0254 mm/r would be a good selection for machining only a few parts, but if the number of components to machine becomes important, a feed rate such as this is not advisable.…”

The Sintering Temperature Effect on the Shrinkage Behavior of Cobalt Chromium Alloy

“…P/M techniques were initially developed to overcome problem of the alignment of carbide in strings which occur in wrought processing (Gimenez et al, 2008). Other advantage of Powder Metallurgy (P/M) is the ability to fabricate of the components with complex geometries (Robert-Perron et al, 2005). In fact, there were also several studies on the tensile, impact and fatigue resistance of the P/M materials which has shown good results (Abdoos et al, 2009;Sudhakar, 2000;Cristofolini et al, 2010).…”