Evaluation of lubricants without zinc phosphate precoat in multi-stage cold forging

Wang, Z.G.; Komiyama, Shinobu; Yoshikawa, Yasuharu; Suzuki, Tatsujiro; Osakada, Kozo

doi:10.1016/j.cirp.2015.04.130

Cited by 49 publications

(19 citation statements)

References 5 publications

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“…Since solid lubricants can effectively improve anti-seizure performance, they have been widely applied as an additive in lubrication coatings used for cold forging processing. In general, a solid lubricant has a cleavage plane in its chemical structure; hence, it can cleave and extend smoothly on the friction surface and coat the active fresh surface formed by substrate deformation [1,2]. Therefore, solid lubricant is an indispensable ingredient for lubrication coatings, especially under severe conditions of high processing load and high surface expansion rate.…”

Section: Introductionmentioning

confidence: 99%

Intercalation Technology for Preparing a Mica–Organic Hybrid Solid Lubricant and Spectroscopic Evaluation of Its Lubrication Mechanism

Komiyama

Sasaki

2019

Tribology Online

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The lubrication behavior of mica-alkyl ammonium cation hybrid solid lubricants fabricated via an intercalation reaction was evaluated by reciprocating sliding tests, and the lubrication mechanism was investigated from the viewpoint of interlayer adhesion strength by Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Evaluation of hybrid micas with three alkyl ammonium cations, which have different lengths and numbers of alkyl chains, indicated that the friction coefficient decreased from 0.4-0.5 to a minimum of 0.12 with increase in the length and the number of alkyl chains of the organic cations. The results of X-ray diffraction revealed that the intercalated organic cations increase the d-spacing of mica, and the effect became prominent with increase in the length and the number of alkyl chains. The results of FTIR and XPS analyses indicated that the interlayer adhesion strength of mica is weakened with increase in the d-spacing, which correlated well with the results of friction coefficient.

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Section: Introductionmentioning

confidence: 99%

Intercalation Technology for Preparing a Mica–Organic Hybrid Solid Lubricant and Spectroscopic Evaluation of Its Lubrication Mechanism

Komiyama

Sasaki

2019

Tribology Online

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“…Wang et al investigated surface texturing of billets in upsetting and ironing processes and found a higher lubricant capacity for textured surfaces. An investigation on the dependency of lubricant capacity or forming force reduction in favor or the surface roughness or hardness was not done [13]. Groche et al investigated the influence of surface textures on forming tools in order to reduce friction and wear.…”

Section: Introductionmentioning

confidence: 99%

“…The understanding of the mechanisms between a textured workpiece and the forming tool helps to enable a dry metal forming process, see Fig. 1 [13]. In former investigation the influence of surface textured workpieces on the use of self-lubricating PVD-coated tools is done [19].…”

Section: Introductionmentioning

confidence: 99%

Influence of surface integrity on the plastic flow in analogous testing of 42CrMo4

et al. 2018

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Surface modification of workpieces for cold forming processes is common in industrial practice. Specific surface topographies manufactured by means of shot peening form lubricant pockets, which provide a continuous lubricating film throughout the process. Furthermore, hydrostatic as well as hydrodynamic lubrication effects emerge, which further reduce the friction during the process and protect the tool from wear effects. These effects are well researched and applied in order to enable cold forming processes. In dry forming processes, no lubricants are used, and the positive lubrication effects do not appear. Surface modifications by shot peening or knurling change surface integrity in terms of hardness, residual stresses and geometry. The effects of the changed surface integrity on the forming process are not researched. In tribometer tests, a hard and rough surface texture lead to a lower frictional shear stress, whereas a rather smooth and hard surface texture leads to a lower punch force in an extrusion process. The mechanisms between surface textures and the smoothing and forming process are unknown. Furthermore, findings of the tribometer tests cannot be fully transferred to the extrusion process. As in tribometer tests a pin is used as tool and in extrusion a whole die, a discrepancy between the most suitable surface texture for a friction reduction results out of different flow conditions. Still, the tribometer tests give a first reference on a surface pretreament. The paper deals with an investigation of surface textures in order to distinguish characteristics of surface textures respectively a friction reduction. By means of indentation tests of the quenched and tempered steel 42CrMo4 the plastic flow in dependency of different surface integrities are researched. The results show which characteristics help to lower the punch force the most, so for further investigations an optimized surface modification is set up in order to enable a dry metal forming process.

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“…Figure 3 shows a schematic illustration of the tribometer, which consists of an upper punch, lower punch and three bearing balls [2,16]. Table 2 provides details of the experimental conditions.…”

Section: Evaluation Of Lubricitymentioning

confidence: 99%

“…In general, solid lubricants are used as an additive in oil, grease, and lubrication coatings. Solid lubricants work by preventing direct contact between the metal surface and die, thereby ensuring smooth processing in the frictional interface between them [1,2].…”

Section: Introductionmentioning

confidence: 99%

Effect of Surface Roughness on Improved Lubricity under an Ironing Condition Using a Synthetic Mica-Organic Intercalation Compound

et al. 2017

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It is well known that the surface roughness of metal substrates considerably influences the tribological properties of solid lubricants. In this study, the surfaces of metal substrates were modified by wet-blasting and polishing, and the lubrication performance of synthetic mica-organic intercalation compounds on these substrates was evaluated using an upsetting-ironing type tribometer. Wet-blasted substrates lubricated with synthetic mica exhibited the best anti-seizure ability, whereas a lubricated polished metal surface produced the worst results. Scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS) revealed that concavities prepared by wet-blasting still remained on the ironed substrate surface, and the intercalated synthetic mica trapped in concavities was supplied to the flat areas as ironing advanced across the substrate surface. Furthermore, EDS and Fourier-transform infrared spectroscopy (FTIR) analysis showed that intercalated synthetic mica extended on the ironed surface while releasing organic compounds from its interlayer spaces. As the ironing process continued to progress, the initial concavities gradually became shallow, but they did not completely flatten. Therefore, a roughened surface is more advantageous for achieving improved lubricity due to the continuous supply of solid lubricant from concavities to the flattened areas where seizure is likely to take place.

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Evaluation of lubricants without zinc phosphate precoat in multi-stage cold forging

Cited by 49 publications

References 5 publications

Intercalation Technology for Preparing a Mica–Organic Hybrid Solid Lubricant and Spectroscopic Evaluation of Its Lubrication Mechanism

Intercalation Technology for Preparing a Mica–Organic Hybrid Solid Lubricant and Spectroscopic Evaluation of Its Lubrication Mechanism

Influence of surface integrity on the plastic flow in analogous testing of 42CrMo4

Effect of Surface Roughness on Improved Lubricity under an Ironing Condition Using a Synthetic Mica-Organic Intercalation Compound

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