scholarly journals A Study on DLC Tool Coating for Deep Drawing and Ironing of Stainless Steel

2018 ◽  
Vol 767 ◽  
pp. 181-188 ◽  
Author(s):  
Esmeray Üstünyagiz ◽  
Mohd Hafis Sulaiman ◽  
Peter Christiansen ◽  
Chris Valentin Nielsen ◽  
Niels Bay

The trend in metal forming tribology is to develop new tribo-systems including new lubricants, tool materials and tool coatings in order to substitute environmentally hazardous lubricants by environmentally friendly tribo-systems. In preliminary testing the limits of lubrication of new tribo-systems for sheet forming production, it is advantageous to use dedicated simulative tribo-tests. This paper studies the influence of tool coatings on deep drawing operations using the Bending Under Tension (BUT) test and also under more severe tribological conditions by adopting the Strip Reduction Test (SRT) to replicate industrial ironing of deep drawn, stainless steel parts. Non-hazardous tribo-systems in form of a double layer Diamond-like coated tool applied under dry condition or with an environmentally friendly lubricant were investigated via emulating industrial process conditions in laboratory tests. Experiments revealed that the double layer coating worked successfully, i.e. with no sign of galling, when it was used with environmentally friendly lubricants, whereas the results were more prone to galling under dry condition.

Biologia ◽  
2013 ◽  
Vol 68 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Basar Karaca ◽  
Nefise Akcelik ◽  
Mustafa Akcelik

AbstractIn the present study the biofilm-forming characteristics of 99 serotyped (DMC strains) and 41 genus level-identified (IS strains) Salmonella strains originating from Turkey were investigated. The strains were selected based on their ability to show the biofilm morphotype on Congo red agar plates. In addition, all strains were evaluated with regard to properties related to forming pellicle structures, physical differences of pellicles, any changes in the media associated with the formation of pellicles, and the presence of cellulose within the formed biofilm matrix as determined using 366 nm UV light. The Salmonella Typhimurium DMC4 strain was the best producer of biofilm grown on polystyrene microtiter plates (optical density at 595 nm: 3.418). In subsequent experiments industrial process conditions were used to investigate different morphotyped Salmonella strains’ biofilm-forming capability on stainless steel, a commonly preferred surface for the food industries, and on polystyrene surfaces. The effect of other important industrial conditions, such as temperature (5, 20, 37°C), pH (4.5, 5.5, 6.5, 7.4) and NaCl concentration (0.5, 1.5, 5.5, 10.5%) on the production of biofilm of the different morphotyped Salmonella strains (DMC4; red, dry and rough morphotyped S. Typhimurium, DMC12; brown, dry and rough morphotyped S. Infantis, DMC13; pink, dry and rough morphotyped S. subsp. Roughform) were also assessed. On the other hand, pH values exhibited variable effects on biofilm-forming features for different Salmonella strains on both polystyrene and stainless steel surfaces.


2013 ◽  
Vol 554-557 ◽  
pp. 1501-1508 ◽  
Author(s):  
Philipp Schmid ◽  
Mathias Liewald

Heat transfer coefficients are playing an important role in forming of metastable stainless steel sheets. Metastable austenitic stainless steels are highly influenced by heating of forming tools due to generation of latent heat during forming process. Strain-induced martensite formation and hence the TRIP-effect is directly coupled with the temperature development within forming tools as well as the temperature induced by heat controlled tools. Measurements of heat development in serial deep drawing processes are showing the need for an accurate determination of heat transfer coefficients considering actual process conditions. Heat transfer coefficients were determined with a simple and easy applicable measurement device for tool materials AMPCO 25 and cold work tool steel EN 1.2379 in combination with aluminum, austenitic EN 1.4301 and ferritic EN 1.4016 stainless steel grades. Special attention was paid to production-related individual influences such as surface conditions, lubrication and deep drawing film. Experiments were accomplished between 1-15 N/mm² showing high influence of intermediate media on heat transfer between forming tool and part and serve as boundary conditions for fully thermo-mechanical coupled forming simulations. A strong influence of deep drawing film, lubrication and surface pressure on heat exchange could be determined and this basic knowledge is seen as mandatory for dimensioning of heat controlled metal forming tools. Finally the experimental determined results are discussed and compared to common heat transfer models and similar experiments from literature.


Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1449
Author(s):  
Miha Hren ◽  
Tadeja Kosec ◽  
Mari Lindgren ◽  
Elina Huttunen-Saarivirta ◽  
Andraž Legat

Equipment made of different stainless steels is often used in the hydrometallurgical processing industry. In this study, an electrical resistance sensor was developed for monitoring corrosion in acidic solutions at high temperature. Two types of stainless steel were used as the electrode materials, namely grade 316L stainless steel (EN 1.4404) and grade 2507 duplex stainless steel (EN 1.4410). The materials and sensors were exposed to a 10% H2SO4 solution containing 5000 mg/L of NaCl at various temperatures. Results from the sensors were verified using electrochemical techniques and postexposure examination. Results showed that the microstructure played an important role in the interpretation of corrosion rates, highlighting the importance of using an appropriate stainless steel for the production of sensors. Electrochemical tests and postexposure examination both showed that the grade 2507 had a significantly lower corrosion rate compared to the grade 316L. Under industrial‑process conditions, the results for the grade 2507 sensor were promising with respect to sensor durability and performance, despite the extremely harsh operating environment.


1982 ◽  
Vol 68 (6) ◽  
pp. 649-657 ◽  
Author(s):  
Kiyohiko NOHARA ◽  
Kenji WATANABE ◽  
Yutaka ONO ◽  
Nobuo OHASHI

Alloy Digest ◽  
2002 ◽  
Vol 51 (1) ◽  

Abstract Allegheny Ludlum Type 305 (S30500) stainless steel is used for applications requiring a low rate of work hardening during severe cold-forming operations such as deep drawing. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on high temperature performance and corrosion resistance as well as heat treating and joining. Filing Code: SS-840. Producer or source: Allegheny Ludlum Corporation.


Alloy Digest ◽  
1999 ◽  
Vol 48 (9) ◽  

Abstract ALZ 305 is an austenitic stainless steel with excellent formability and good corrosion resistance, toughness, and mechanical properties. The higher amount of nickel in this grade enables high deep-drawing deformation without intermediate annealing. This datasheet provides information on composition, physical properties, and elasticity. It also includes information on corrosion resistance as well as forming, heat treating, and joining. Filing Code: SS-762. Producer or source: ALZ nv.


2021 ◽  
Vol 34 (1) ◽  
Author(s):  
Jingwei Zhao ◽  
Tao Wang ◽  
Fanghui Jia ◽  
Zhou Li ◽  
Cunlong Zhou ◽  
...  

AbstractIn the present work, austenitic stainless steel (ASS) 304 foils with a thickness of 50 µm were first annealed at temperatures ranging from 700 to 1100 ℃ for 1 h to obtain different microstructural characteristics. Then the effects of microstructural characteristics on the formability of ASS 304 foils and the quality of drawn cups using micro deep drawing (MDD) were studied, and the mechanism involved was discussed. The results show that the as-received ASS 304 foil has a poor formability and cannot be used to form a cup using MDD. Serious wrinkling problem occurs on the drawn cup, and the height profile distribution on the mouth and the symmetry of the drawn cup is quite non-uniform when the annealing temperature is 700 ℃. At annealing temperatures of 900 and 950 ℃, the drawn cups are both characterized with very few wrinkles, and the distribution of height profile, symmetry and mouth thickness are uniform on the mouths of the drawn cups. The wrinkling becomes increasingly significant with a further increase of annealing temperature from 950 to 1100 ℃. The optimal annealing temperatures obtained in this study are 900 and 950 ℃ for reducing the generation of wrinkling, and therefore improving the quality of drawn cups. With non-optimized microstructure, the distribution of the compressive stress in the circumferential direction of the drawn foils becomes inhomogeneous, which is thought to be the cause of the occurrence of localized deformation till wrinkling during MDD.


2005 ◽  
Vol 488-489 ◽  
pp. 453-456 ◽  
Author(s):  
Shi Hong Zhang ◽  
Yong Chao Xu ◽  
G. Palumbo ◽  
S. Pinto ◽  
Luigi Tricarico ◽  
...  

Comparing the formability with each other, extrusion and various rolling experiments were carried out to make fine-grained AZ31 Mg sheets, and uni-axial tensile tests were carried out at different strain rates and temperatures to investigate the effect of different variables. A warm deep drawing tool setup with heating elements, which were distributed under the die surface and inside the blank holder, was designed and manufactured, and deep drawing was performed. Extruded Mg alloy AZ31 sheets exhibit the best deep drawing ability when working in the temperature range 250-350°C. Extruded and rolled sheets of 0.8 mm thick were also deep drawn in the lower temperature range 105-170°C,showing good formability and reaching a Limit Drawing Ratio up to 2.6 at 170°C for rolled sheets. At last, a sheet cup 0.4 mm thick was deep drawn successfully at 170 °C.


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