The Influence of Cryogenic Coolants in Machining of Ti–6Al–4V

Abstract

Machining of titanium alloy TÍ-6AI-4V is a challenging task because of the greatly increased cutting temperature that results in short tool life. Numerous attempts have been made in the past by employing various cutting fluids for machining purpose, including liquid nitrogen (LN2) as the cryogenic coolant. This study deals with the influence of cryogenic coolants, especially LN2 end carbon dioxide (CO2). in machining ofTi-6Al-4V and its effects on cutting temperature, cutting forces, surface roughness, chip morphology, and tool wear. The results obtained in cryogenic machining are compared with that of dry and wet machining. Cutting temperature was reduced to an extent of 36% and 47% in cryogenic CO2 machining and cryogenic LN2 machining in comparison with wet machining. The application of CO2 produced reduced cutting forces up to 24% and improved surface flnish up to 48% compared to cryogenic LN2 machining. It also produced better chip control and minimized tool wear than dry. wet, and LN2 machining.

Influence of single and dual cryogenic jets on machinability characteristics in turning of Ti-6Al-4V

“…Similarly, Strano et al 40 claimed that all components of cutting forces reduced due to the effective lubrication created by cryogenic nitrogen than the water–oil flood coolant. Jerold and Kumar 41 showed that the cutting force was reduced by 9%–22% compared to wet cooling using cryogenic condition. One can see that in all cases the cryogenic condition reduced cutting forces than the wet condition, that is, it reduced the consumption of specific cutting energy.…”

“…From literature, it is appreciable that the traditional flood cooling is unlikely to bring the best machining performance due to the ineffective cooling by flood cooling. Some researchers have pointed out this ineffectiveness and presented superiority of cryogenic cooling than wet cooling; for instance, Dhananchezian and Kumar 39 claimed 62% and Jerold and Kumar 41 reported 47% reduction of cutting temperature using cryogenic cooling over conventional wet cooling. The results of this study have also reported the reduction of cutting temperature by the use of single jet cryogenic cooling and duplex jets cryogenic cooling, provided the duplex jets have reduced the temperature in greater quantity due to the simultaneous cooling of rake and flank surfaces of tool.…”

“…The surface roughness generated in wet condition, in machining Ti-6Al-4V, is higher than that of cryogenic condition, reported by researchers. 39,41,46 Prime reason of this occurrence is the failure to reduce the temperature and happening of adhesion of particles (i.e. chip debris) to the machined surface.…”

The Performance of Diamond-Like Carbon Coated Drills in Thermally Assisted Drilling of Ti-6Al-4V

“…To alleviate this problem and improve the tool life, studies have considered, in addition to the use of conventional flooded coolants, the application of cryogenic coolants that can remove the heat effectively from the cutting zone. Minimum quantity lubrication cutting technique has also been considered [14][15][16][17][18][19].…”

Evaluation of cutting force and surface roughness in high-speed milling of compacted graphite iron

“…Nevertheless, reports on the performance of cryogenic cooling when machining of CGI are very limited. It was very common that an external spray nozzle is used to supply LN2 to the cutting tool as shown reported by many researchers since year 2001 until now [13,[16][17][18][19][20]. By this way, the surface hardness of the workpiece material may increase due to the excessive LN2 spray.…”