Analysis of the Effectiveness of Technological Lubricants with the Addition of Boric Acid in Sheet Metal Forming

Abstract

One of the main problems during sheet metal forming is the reduction in coefficient of friction and separation of contact surfaces in order to eliminate buildups of the formed material on the forming tools. For this purpose, technological lubricants based on mineral or synthetic oils are usually used. Unfortunately, their removal from the drawn parts and their subsequent utilization pose many problems and are expensive. Environmentally benign lubricants based on vegetable oils with the addition of boric acid could be an effective alternative to lubricants based on mineral and synthetic oils; however, the solubility of boric acid in oils is limited. Therefore, the paper proposes new, effective, and environmentally friendly methods for applying boric acid to the metal sheet by spraying it on a thin rapeseed oil layer previously applied to the metal sheet or by spraying a 25% solution of boric acid in methyl alcohol onto the sheet. The effectiveness of such lubrication was assessed on the basis of the so-called strip drawing test, Erichsen cupping test, and formation of cylindrical drawn parts in industrial conditions. The tests showed that the addition of boric acid was most effective for forming the DC01 steel sheet, reducing the coefficient of friction by about 60% compared to base oil lubrication. Although its usefulness is lower in the case of other frictional pairs, it eliminates the phenomenon of the formed material sticking to the tool, thus extending the life of the forming tools. The use of the proposed solution reduces production costs and indirectly boosts environmental protection. Moreover, an explanation of the tribological mechanism contributing to the lubrication action of boric acid is given.

Effects of Deep Cryogenic Treatment on Friction and Wear of EN24 Steel Against Alumina Under Dry and Lubrication Conditions

“…The AsRec-EN24, ConHeatTreat-EN24, and DeepCryoTreat-EN24 have the stronger O peaks on all the EDX spectra of their wear tracks under 1 N (Figures 9d-f) than under 5 N (Figures 9g-i), which can be correlated to their higher friction under 1 N (Figure 5). On the EDX spectra measured on the wear tracks of the lubricated AsRec-EN24, ConHeatTreat-EN24, and DeepCryoTreat-EN24 (Figures 9j-l), the C peaks are not apparently discriminated from overlapped surrounding peaks and the O peaks are found weaker compared to those tested dry (Figures 9g-i) because the MO apparently suppresses the frictional heat that is responsible for the oxidation process [44].…”

The Comparison of the Multi-Layer Artificial Neural Network Training Methods in Terms of the Predictive Quality of the Coefficient of Friction of 1.0338 (DC04) Steel Sheet

“…Adamus et al [32] developed environmentally friendly methods for applying H3BO3 to a metal sheet by spraying it onto a thin layer of rapeseed oil that had been previously applied to the metal sheet surface. Trzepieci ński et al [33] tested the lubrication efficiency of non-edible oils with the most frequently tested edible oils (sunflower and rapeseed) in a steel-steel contact pair.…”

Effect of Process Variables on Interface Friction Characteristics in Strip Drawing of AA 5182 Alloy and Its Formability in Warm Deep Drawing

“…However, the frictional characteristics in deep drawing are very critical in warm forming because temperature, sliding speed, lubrication, and binder force affect the interface friction in the flange and die corner regions. The friction and galling in forming processes are known to be affected by various parameters in the sliding contact region, including contact pressure [8,9], sliding velocity, temperature, tool geometry, pre-straining [10], the sliding surfaces of the contact pair [11], and lubricant [12,13]. The adhesion of aluminum alloys to tool surfaces is enhanced during warm forming.…”