https://escholarship.org/content/qt6226v74d/qt6226v74d.pdf?t=qki0rx

Synergetic effects of surface texturing and solid lubricants to tailor friction and wear – A review

An extended structure zone diagram is proposed that includes energetic deposition, characterized by a large flux of ions typical for deposition by filtered cathodic arcs and high power impulse magnetron sputtering. The axes are comprised of a generalized homologous temperature, the normalized kinetic energy flux, and the net film thickness, which can be negative due to ion etching. It is stressed that the number of primary physical parameters affecting growth by far exceeds the number of available axes in such a diagram and therefore it can only provide an approximate and simplified illustration of the growth condition?structure relationships.

/pdf/a-structure-zone-diagram-including-plasma-based-deposition-2p0bkpz4ru.pdf

A structure zone diagram including plasma based deposition and ion etching - eScholarship

Sheet metal forming (SMF) is one of the most popular technologies for obtaining finished products in almost every sector of industrial production, especially in the aircraft, automotive, food and home appliance industries. Parallel to the development of new forming techniques, numerical and empirical approaches are being developed to improve existing and develop new methods of sheet metal forming. Many innovative numerical algorithms, experimental methods and theoretical contributions have recently been proposed for SMF by researchers and business research centers. These methods are mainly focused on the improvement of the formability of materials, production of complex-shaped parts with good surface quality, speeding up of the production cycle, reduction in the number of operations and the environmental performance of manufacturing. This study is intended to summarize recent development trends in both the numerical and experimental fields of conventional deep-drawing, spinning, flexible-die forming, electromagnetic forming and computer-controlled forming methods like incremental sheet forming. The review is limited to the considerable changes that have occurred in the SMF sector in the last decade, with special attention given to the 2015–2020 period. The progress observed in the last decade in the area of SMF mainly concerns the development nonconventional methods of forming difficult-to-form lightweight materials for automotive and aircraft applications. In evaluating the ecological convenience of SMF processes, the tribological aspects have also become the subject of great attention.

/pdf/recent-developments-and-trends-in-sheet-metal-forming-29um1mszus.pdf

Recent Developments and Trends in Sheet Metal Forming

Optimization of bionic textured parameter to improve the tribological performance of AISI 4140 self-lubricating composite through response surface methodology

Efficacy of surface microtexturing in enhancing the tribological performance of polymeric surfaces under starved lubricated conditions

Influence of sheet metal texture on the adhesive wear and friction behaviour of EN AW-5083 aluminum under dry and starved lubrication

Dry sheet metal forming of aluminum by smooth DLC coatings – a capable approach for an efficient production process with reduced environmental impact

Dry forming processes are associated with major challenges, especially when it comes to aluminum as the workpiece material. Major losses in process quality and robustness occur when lubricants are spared. This is due to the high adhesion tendency of aluminum towards common tool materials. Nanoscopically smooth coatings based on amorphous hydrocarbons (a-C:H) can significantly reduce wear. Further preliminary investigations have shown that a reduction of the roughness of a mill-finished sheet results in a significant improvement with regard to the friction and wear behavior in the strip drawing test. These tests are now transferred to a real workpiece. First, the different zones of the deep drawing process are modeled in the strip drawing test and coefficients of friction are derived. Flawless deep drawing tests can be carried out with nanoscopically smooth a-C:H coatings. By polishing the sheets and using the a-C:H coated tools without further surface treatment, the dry friction and wear are reduced, but compared with experiments on smoothened a-C:H coatings, the necessary process forces are higher and may lead to rupture of the aluminum sheet.

/pdf/dry-deep-drawing-of-aluminum-and-the-influence-of-sheet-1solnkhp5v.pdf

Dry Deep Drawing of Aluminum and the Influence of Sheet Metal Roughness

Recent investigations demonstrated the applicability of diamond-like carbon (DLC)-coated tools for dry forming of aluminum, which is a challenging application field due to the high adhesion tendency of aluminum. An exceptionally low roughness of the coated forming tool is required to prevent adhesion-induced tool failure. To establish dry forming of aluminum in industrial production processes, efficient methods must be developed to manufacture DLC-coated forming tools with reproducible high surface quality. This paper illustrates two DLC coating processes that are especially optimized for deposition of nanoscopically smooth DLC tool coatings. Two optimized coating systems were deposited, characterized, and subsequently evaluated using application-oriented strip drawing tests to validate their performance in comparison with a state-of-the-art coating system. One coating process showed high potential for production of DLC-coated forming tools with the required surface quality.

/pdf/deposition-of-nanoscopically-smooth-dlc-tool-coatings-for-299bw58kv4.pdf

Felix Flegler

Papers

Influence of sheet metal texture on the adhesive wear and friction behaviour of EN AW-5083 aluminum under dry and starved lubrication

Dry sheet metal forming of aluminum by smooth DLC coatings – a capable approach for an efficient production process with reduced environmental impact

Dry Deep Drawing of Aluminum and the Influence of Sheet Metal Roughness

Deposition of Nanoscopically Smooth DLC Tool Coatings for Dry Forming of Aluminum Sheets