scholarly journals Tribological Performance of Environmentally Friendly Bio-Degradable Lubricants Based on a Combination of Boric Acid and Bio-Based Oils

Materials ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 3892
Author(s):  
Tomasz Trzepieciński
Keyword(s):  
Boric Acid ◽  
Sheet Metal ◽  
Coefficient Of Friction ◽  
Vegetable Oils ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Low Carbon Steel ◽  
Environmentally Friendly ◽  
Low Carbon ◽  
The Coefficient Of Friction

Finding effective and environmentally friendly lubrication to use in sheet metal forming operations presents a substantial environmental and economic challenge to the automotive industry. This paper examines the effectiveness of different lubricants in the reduction of the coefficient of friction (COF) in the process of sheet metal forming of the low carbon steel sheets. These lubricants are based on a combination of boric acid (H3BO3) and edible vegetable oils, both of which are natural and environmentally friendly. To evaluate the friction characteristics of the lubricants in a forming operation, a strip drawing friction test is used. This test consisted in drawing a specimen in the form of a sheet metal strip between two non-rotating counter-samples with radii of 200 and 10 mm. The effectiveness of environmentally friendly lubricants in reducing the COF was compared to the traditional petroleum-based lubricants which are used in sheet metal-forming operations. The effect of lubricant conditions and tool surface roughness on the value of COFs is studied. It was found that palm oil in both configurations of countersample radius, both as pure oil and with the addition of 5 wt.% of H3BO3, was the most effective in lowering the coefficient of friction. In most of the conditions analysed, the addition of boric acid into vegetable oils leads to an increase in the lubrication efficiency by up to 15% compared to pure oils. The effectiveness of lubrication by olive and rapeseed oils in decreasing the frictional resistances clearly depends on the nominal pressure applied.

Investigating Bauschinger Effect and Plastic Hardening Characteristics of Sheet Metal under Cyclic Loading

2017 ◽  
Vol 4 (2) ◽  
pp. 1-14 ◽  
Author(s):  
Jasri Mohamad
Keyword(s):  
Cyclic Loading ◽  
Sheet Metal ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Bauschinger Effect ◽  
Low Carbon Steel ◽  
Cyclic Hardening ◽  
Low Carbon ◽  
Forming Process ◽  
Metal Forming Process

To improve sheet metal forming process simulation using finite element method, there is a need to incorporate an appropriate constitutive equation capable of describing the Bauschinger effect and the so-called cyclic transient, derived from a near to actual sheet metal forming process testing tool. A cyclic loading tool has been developed to test and record the characteristics of sheet metal deformation by investigating the Bauschinger effect factors (BEF) and cyclic hardening behaviour. Experimental investigation conducted on low carbon steel and stainless steel demonstrates that the tool is able to record sheet metal behaviour under cyclic loading. The results are analysed for signs of the Bauschinger effect and cyclic hardening effect. It was found that the Bauschinger effect does occur during bending and unbending loadings in sheet metal forming process.

scholarly journals Contact pressure and sliding velocity ranges in sheet metal forming simulations

2021 ◽  
Author(s):  
Joseba Cillaurren ◽  
Lander Galdos ◽  
Mario Sanchez ◽  
Alaitz Zabala ◽  
Eneko Saenz de Argandoña ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Contact Pressure ◽  
Sheet Metal ◽  
Coefficient Of Friction ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Sliding Velocity ◽  
Wide Range ◽  
The Coefficient Of Friction ◽  
Friction Models

In the last few years many efforts have been carried out in order to better understand what the real contact between material and tools is. Based on the better understanding new friction models have been developed which have allowed process designers to improve numerical results in terms of component viability and geometrical accuracy. The new models define the coefficient of friction depending on different process parameters such as the contact pressure, the sliding velocity, the material strain, and the tool temperature. Many examples of the improvements achieved, both at laboratory scale and at industrial scale, can be found in the recent literature. However, in each of the examples found in the literature, different ranges of the variables affecting the coefficient of friction are covered depending on the component analysed and the material used to produce such component. The present work statistically analyses the contact pressure and sliding velocity ranges achieved during numerical simulation (FEM) of sheet metal forming processes. Nineteen different industrial components representing a high variety of shapes have been studied to cover a wide range of casuistic. The contact pressure and sliding velocity corresponding to typical areas of the tooling have been analysed though numerical simulation in each case. This study identifies the ranges of contact-pressure and sliding velocities occurring in sheet metal forming aimed to set the characterization range for future friction studies.

Correlating the Features of Topography to Friction by Sliding Experiments

2008 ◽  
Author(s):  
Anirudhan Pottirayil ◽  
Pradeep L. Menezes ◽  
Satish V. Kailas
Keyword(s):  
Sheet Metal ◽  
Coefficient Of Friction ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Work Piece ◽  
Manufacturing Processes ◽  
Experimental Procedure ◽  
The Coefficient Of Friction ◽  
Soft Metal

Friction can influence the quality of the finished product to a large extent in certain manufacturing processes. Sheet metal forming is a particular case, where the friction between the hard-die and the relatively soft work-piece can be extremely important. Under such conditions, topography of the harder surface can influence the resistance to traction at the interface. This paper discusses about the correlation between certain features of the surface topography and coefficient of friction based on experiments involving sliding of a few soft metal pins against a harder material. A brief description of the experimental procedure and the analysis are presented. A hybrid parameter which encapsulates both the amplitude features as well as the relative packing of peaks is shown to correlate well with the coefficient of friction.

Influence of Segmented Blank Holder for Rectangular Box Drawing

2011 ◽  
Vol 189-193 ◽  
pp. 2495-2498
Author(s):  
Xi Ning Li ◽  
L.X. Liu ◽  
J.P. Wang ◽  
C.Y. Jiang ◽  
Z.Q. Wang
Keyword(s):  
Sheet Metal ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Orthogonal Experiment ◽  
Low Carbon Steel ◽  
Low Carbon ◽  
Forming Process ◽  
Blank Holder ◽  
Forming Simulation ◽  
Straight Segments

Blanker holder force (BHF) is one of the important parameters in sheet metal forming process, which is loaded by blanker holder in order to avoid wrinkling. With the development of technology, segmented blanker holder is applied to complicated product forming in order to improve the parts quality. On the basis of analyzing the character of rectangle box forming, the blank holder was divided eight portions, including 2 long straight segments, 2 short straight segments and 4 corners, which each part can separately move. Then the forming simulation of the low carbon steel rectangular box with segmented constant BHF was conducted using orthogonal experiment and considering test conditions. After the results were analyzed according to the thinnest level of the parts, the influence of the segmented blank holder on rectangular box forming was obtained. It indicates that the segmented blank holder has the ability of the local control to sheet metal forming, and can effectively adjust material flow and the strain distribution.

A Novel Particulate-Fluid Lubrication for Environmentally Benign Forming Processes

2005 ◽  
Author(s):  
M. Lovell ◽  
C. F. Higgs ◽  
A. J. Mobley
Keyword(s):  
Boric Acid ◽  
Sheet Metal ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Canola Oil ◽  
Environmentally Friendly ◽  
Environmentally Benign ◽  
Metal Parts ◽  
Sheet Metal Parts ◽  
Oil Formulation

Forming sheet metal parts in the absence of lubricants is not practical in production operations. In practice, large amounts of liquid and grease lubricants are utilized in sheet forming to ensure that there is sufficient lubrication to reduce asperity interaction and increase formability. In the present investigation, an alternative environmentally friendly lubricant is introduced for sheet metal forming processes. This lubricant is based on a combination of boric acid and canola oil, both of which are natural, environmentally friendly, and have independently demonstrated good lubrication potential. Utilizing a specialized sheet metal stretching apparatus, an optimized boric acid and canola oil formulation was evaluated for use in metal forming operations. Based on the experimental results, the optimized lubricant shows substantial potential for providing the manufacturing community with a commercially viable and environmentally friendly lubricant that will eliminate expensive disposal costs.

scholarly journals Methods of determination of frictional resistances in sheet metal forming of car body sheets

2018 ◽  
Vol 19 (6) ◽  
pp. 756-760
Author(s):  
Tomasz Trzepieciński ◽  
Irena Nowotyńska
Keyword(s):  
Sheet Metal ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Complex Function ◽  
Forming Process ◽  
The Coefficient Of Friction ◽  
Displacement Speed ◽  
Almost All ◽  
Lubrication Conditions

The friction phenomenon existed in almost all plastic working processes, in particular sheet metal forming, is a complex function of the material's properties, parameters of the forming process, surface topography of the sheet and tools, and lubrication conditions. During the stamping of the drawpieces there are zones differentiated in terms of stress and strain state, displacement speed and friction conditions. This article describes the methods for determining the value of the coefficient of friction in selected areas of sheet metal and presents the drawbacks and limitations of these methods.

scholarly journals Advanced Friction Modeling in Sheet Metal Forming

2011 ◽  
Vol 473 ◽  
pp. 715-722 ◽  
Author(s):  
J. Hol ◽  
M.V. Cid Alfaro ◽  
T. Meinders ◽  
J. Huétink
Keyword(s):  
Finite Element ◽  
Sheet Metal ◽  
Coefficient Of Friction ◽  
Surface Texture ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Large Scale ◽  
Friction Model ◽  
Micro Scale ◽  
Forming Simulations

The Coulomb friction model is frequently used for sheet metal forming simulations. This model incorporates a constant coefficient of friction and does not take the influence of important parameters such as contact pressure or deformation of the sheet material into account. This article presents a more advanced friction model for large-scale forming simulations based on the surface changes on the micro-scale. When two surfaces are in contact, the surface texture of a material changes due to the combination of normal loading and stretching. Consequently, shear stresses between contacting surfaces, caused by the adhesion and ploughing effect between contacting asperities, will change when the surface texture changes. A friction model has been developed which accounts for these microscopic dependencies and its influence on the friction behavior on the macro-scale. The friction model has been validated by means of finite element simulations on the micro-scale and has been implemented in a finite element code to run large scale sheet metal forming simulations. Results showed a realistic distribution of the coefficient of friction depending on the local process conditions.

Effects of Rolling Direction and Lubricant on Friction in Sheet Metal Forming

2009 ◽  
Vol 131 (4) ◽  
Author(s):  
Xiaojun Liu ◽  
Mathias Liewald ◽  
Dina Becker
Keyword(s):  
Sheet Metal ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Rolling Direction ◽  
Alloy Sheet ◽  
Friction Behavior ◽  
Drawing Test ◽  
Strip Drawing ◽  
The Coefficient Of Friction ◽  
Surface Microstructures

Lubrication and friction at workpiece-tool interface play an important role in product quality control of sheet metal forming process. Surface microstructures of sheets have a great influence on the development of lubrication films. In order to investigate the effects of the rolling direction of aluminum alloy sheet and lubricant on the friction behavior in sheet metal forming, strip drawing test was used. The sample used was electric discharge texturing (EDT) surface. Lubricants, both with and without additives, were used. The strip drawing tests were performed at angles between the sliding and rolling directions of 0–90 deg. Variations in the sheet surface topography were analyzed by comparing the sheet surface microstructures and its 3D surface parameters before and after the strip drawing test. Results of the strip drawing tests indicate that the kind and amount of lubricant have great influences on friction at the interface, and the lubricant with additives benefits improving the friction behavior between the sheet and the tool. The EDT surface of the aluminum alloy sheet has an anisotropic frictional property during deep drawing process due to different angles between the sliding and rolling directions. When the sliding direction is parallel to the rolling direction, the coefficient of friction has the highest value. When the angle between the sliding and rolling directions increases, the coefficient of friction decreases. The surface microstructure of the sheets after the strip drawing test at different angles between the sliding and rolling directions has been modified, and its 3D surface parameters decrease significantly to a different degree.

The Coefficient of Friction During Hot Rolling of Low Carbon Steel Strips

2002 ◽  
Vol 124 (4) ◽  
pp. 840-845 ◽  
Author(s):  
John G. Lenard ◽  
Leon Barbulovic-Nad
Keyword(s):  
Carbon Steel ◽  
Coefficient Of Friction ◽  
Hot Rolling ◽  
Linear Regression Analysis ◽  
Low Carbon Steel ◽  
Hot Strip Mill ◽  
Low Carbon ◽  
Process Variables ◽  
Steel Strips ◽  
The Coefficient Of Friction

Hot rolling tests were performed on low carbon steel strips with the objective of determining the coefficient of friction as a function of the process variables. The growth of the scale prior to rolling was controlled and the thickness of the layer of scale at the entry remained in the range of 20–100 μm, somewhat higher than in the finishing train of a hot strip mill. Roll separating forces, roll torques, the speed, the reduction and the entry temperature were monitored. The effective coefficient of friction was determined by using a one-dimensional model of the flat rolling process. The coefficient was chosen to allow matching the measured and calculated roll force and the roll torque. An empirical relation, connecting the coefficient of friction to process variables was obtained by non-linear regression analysis.

Sign in / Sign up

Export Citation Format

Share Document