New environmental legislation is forcing companies to realign their use of metalworking fluids in favour of non-polluting cutting environments that will return acceptable tool wear rates and reduced costs. Studies have been undertaken to determine the effectiveness of various environments on tool wear, in order to either reduce or even eliminate totally, the dependency on flood coolants. Industrially reproducible cutting tests were devised, where an EN32 case hardening steel material was turned in a range of different cutting environments and tool life measured. Low oxygen gaseous environments were compared with conventional cutting environments and a 55 per cent flank wear reduction has been recorded using uncoated tooling. (Emerald Group Publishing Limited)

Abstract: Purpose – Cutting fluids despite playing an important role in metal cutting have considerable environmental impact. Inert gaseous metal cutting environments were investigated with the aim of removing soluble oil cutting fluids from metal cutting operations. Design/methodology/approach – Industrially reproducible cutting tests were devised, where an austenitic stainless steel and En32 low carbon steel material was milled in a range of different cutting environments. Tool life was measured for tests carried out in a number of gaseous environments and results were then compared with test results from conventional flood cutting environments. Findings – Low oxygen gaseous environments were compared with conventional cutting environments and a considerable flank wear reduction has been recorded using CVD coated tooling. Additionally flood coolant environments have been seen to promote chemical wear after the initial breakdown of coatings leading to rapid flank wear during milling of both En32 and austenitic stainless steel. Research limitations/implications – Only a limited number of work/tool material combinations have been investigated. A more detailed and exhaustive investigation is required to ascertain the scope of the improvements for a range of tool work combinations. This will assist in understanding the underlying reasoning for the tool life enhancement reported. Practical implications – All experimentation carried out is industrially reproducible. This work, therefore, proposes an environmentally clean alternative to the use of emulsified oils in metal cutting operations in order to exploit cost savings and improved operator working environments. Originality/value – Distinct operational performance improvements have been demonstrated in the form of extended tool life for metal cutting operations performed in a non-polluting cutting environment. These findings could herald widespread advantages within the metal cutting community. (Emerald Group Publishing Limited)

As more stringent environmental legislation is enforced throughout Europe manufacturing businesses, employing metal cutting processes, can no longer ignore the growing importance of environmental aspects relating to cutting fluids. Businesses, through market forces, are being forced into offering a “clean solution” to the metal cutting processes which they operate. Cutting fluids despite playing an important role in metal cutting, have considerable environmental impact. There is a need therefore to understand the role of cutting fluids within the cutting process in order to evaluate possible environmentally friendly alternatives to the use of cutting fluids. In order to achieve this the operating environment in which the process is being carried out, and the consequences of removing the cutting fluid from the process altogether has to be assessed. This paper therefore, reflects on the role of cutting fluid and the implications of their use. Viable methods of reducing cutting fluid consumption are also reported, together with efficient methods of cutting fluid utilisation (e.g. minimum quantity delivery systems). Finally, the difficulties experienced in removing cutting fluids from the metal cutting process are highlighted through the consideration of dry cutting technologies. (Emerald Group Publishing Limited)