45 research outputs found
The Effect of Paraffinic Mineral Oil Lubrication in Cold Forward Extrusion
This paper presents the results of cold forward extrusion modelling and the analysis of the contact sliding behaviour on the die-billet surface by paraffinic mineral oil lubrication with kinematic viscosity of 92 mm2/s at 40 °C. The analysis dealt with the plasticity flow that was investigated by finite element method in order to identify the loads acting on the billet. The finite element analysis of stresses was performed based on load distributions calculated from experimental test. The time behaviour of the displacements on the billet was then used as inputs for the extrusion model. The present method provided good results with reduced computation time. The results of the extrusion model revealed that the zones of high stress situated at the sharp edges of the die, which explains the observed extrusion force to reach a peak value
The Effect of Paraffinic Mineral Oil Lubrication in Cold Forward Extrusion
This paper presents the results of cold forward extrusion modelling and the analysis of the contact sliding behaviour on the die-billet surface by paraffinic mineral oil lubrication with kinematic viscosity of 92 mm2/s at 40 °C. The analysis dealt with the plasticity flow that was investigated by finite element method in order to identify the loads acting on the billet. The finite element analysis of stresses was performed based on load distributions calculated from experimental test. The time behaviour of the displacements on the billet was then used as inputs for the extrusion model. The present method provided good results with reduced computation time. The results of the extrusion model revealed that the zones of high stress situated at the sharp edges of the die, which explains the observed extrusion force to reach a peak value
Influence of tool texture on friction and lubrication in strip reduction
Tool texturing is studied as a method to enhance lubrication and prevent the occurrence of galling. Strip reduction test tools manufactured with longitudinal, shallow pocket geometries oriented perpendicular to the sliding direction are tested. The pockets have small angles to the workpiece surface and varying distance. The experiments show an optimum distance between the pockets to exist that creates table mountain topography with flat plateaus and narrow pockets in between. If the flat plateaus are too narrow, an increase in drawing load and pick-up on the tool plateaus is observed. The same occurs for too wide plateaus. A theoretical friction model supports the experimental findings of an optimum distance between the pockets, where the contribution to friction by mechanical interlocking of the strip in the pockets is limited and lubrication of the plateaus is enhanced by micro-plasto-hydrodynamic lubrication
A study of anti-seizure tool coatings of ironing of stainless steel
Sheet stamping of stainless steel with coated tools alone
may not necessarily impede galling unless hazardous
mineral oils are applied. The present study focuses on an
investigation of a double-layer tool coating structure
applied in a continuous strip reduction test emulating the
conditions in production by ironing. The coating films
consists of Diamond-Like Carbon (DLC) and Hyperlox®.
The results revealed that the DLC/Hyperlox® coating was
functioning effectively without peeling off and galling if
nonhazardous lubricant was applied. This has improved
the tribological system significantly since the coating
allowed the hazardous lubricant to be abandoned.
Numerical analysis using a thermo-mechanical analysis
supports the experimental findings, where the new tribosystem minimizes the temperature at the tool/workpiece interface by reducing the friction
Acoustic emission monitoring of the bending under tension test
Preliminary investigations have shown that acoustic emission has promising aspects as an online monitoring technique for assessment of tribological conditions during metal forming as regards to determination of the onset of galling. In the present study the acoustic emission measuring technique has been applied for online monitoring of the frictional conditions experienced during Bending Under Tension (BUT) testing. The BUT test emulates the forming conditions experienced when drawing sheet material over a die curvature as in deep drawing processes. Monitoring of the developed acoustic emission in BUT testing has been found to describe the frictional conditions during forming well and to allow for accurate assessment of the limits of lubrication
The wettability characteristics of DLC coating for tribological engineering applications
Hard coating deposited to tool steel surface can greatly improve wear resistance and
reduce sticking. Since solid-liquid interactions are present in every lubricated tribological
contact, the present study is aimed to understand the physical phenomena of contact interactions
between the DLC coated surface and the liquid. In this study, double-layer DLC/TiAlN coating
was prepared via Physical Vapour Deposition (PVD) process. The anti-sticking properties were
assessed using contact angle measurements using two liquids with distinctly different viscosity
– water and oil. No significant differences found in the contact angle values for both liquid
properties. The results revealed that the DLC/TiAlN coated tool steel surfaces exhibit
hydrophobic behaviour with high contact angle values. With a lower surface energy of the
DLC/TiAlN coating in comparison to uncoated surface, this suggests that the DLC/TiAlN
coating is a good hard coating candidate since it has a lower adhesion resistance and an improved
release performance
Investigating Fertilizer Spreader Blades for Improved Flow Behaviours and Material Resilience in Palm Plantation Settings
Fertilizer spreaders play a crucial role in evenly distributing granule fertilizer across palm plantations. However, in specific areas where growth conditions are unsuitable, fertilizer application becomes unnecessary. Therefore, this study aims to improve granule fertilizer distribution efficiency through enhanced fertilizer blade design. Using Finite Element (FE) simulation, the stress deformation and deflection of the existing spreader blade were evaluated. Meanwhile, Computational Fluid Dynamics (CFD) simulation was used to investigate the influence of spreader design on fertilizer projection speed and direction in the case of open and closed side discharge. The study revealed that the applied forces increased both the critical stress deformation and deflection. To ensure the fertilizer spreads properly over the desired area, the initial velocity had to be increased proportionally with an increase in the angle of direction. These findings contributed to a deeper understanding of the relationship between fertilizer projection velocity, spreader blade strength, and flow behaviour, enabling the reduction of waste in granule fertilizer, while enhancing the operational efficiency and reliability of fertilizer spreader
Effects of coating and lubrication on friction and wear for metal-to metal application
Friction and wear between sliding surfaces can lead to various issues in industrial applications, such as increased costs, reduced machine lifespan, loss of functionality, energy loss, and decreased system efficiency. To mitigate these problems, lubricants and coatings are commonly employed. This study aims to investigate the impact of coatings and lubrication on friction coefficient, wear volume loss, and lubricant temperature using the block-on-ring wear test. The effectiveness of different coatings (uncoated, DLC, CrN, and TiALN) and lubricants (anti-friction graphene oxide additive oil and strong nano engine oil additive) in reducing friction and wear is evaluated. The block-on-ring tests are conducted under varying loads (6-60 N), speeds (1450 rpm), lubricant volumes (40 ml), and durations (2-20 min). The coefficient of friction is measured using an inline load cell, wear volume loss is determined by weighing the blocks before and after the experiment, and lubricant temperature is monitored using thermocouples. The results indicate that the coefficient of friction decreases with increasing load, while the lubricant temperature rises. Coated blocks exhibit lower wear volume loss compared to uncoated blocks. Overall, the combination of CrN-coated blocks and anti-friction graphene oxide additive oil demonstrates the best tribological performance
Evaluation of the surface roughness and dimensional accuracy of low-cost 3D-printed parts made of PLA–aluminum
Fused deposition modeling (FDM) is currently used in several fields, such as architecture, manufacturing, and medical applications. FDM was initially developed to produce and create prototypes, but the expense appears excessive for producing final products. Nevertheless, in this day and age, engineers have developed a low-cost 3D printer. One of the major issues with lowcost 3D printers is the low dimensional accuracy and high tolerances of the printed products. Herein, different printing parameters, i.e., layer thickness, printing speed, and raster angle, need to be investigated to enhance the surface roughness of the parts produced using FDM. Thus, the present study focuses on investigating the performance of the surface finish produced by FDM by manipulating different parameters such as layer thickness, printing speed, and raster angle. Taguchi’s method, based on the L9 array for experimental design, was employed to elucidate the response variables. The sample model was developed following ISO standards, utilizing polylactic acid (PLA)–aluminum as the filament material. The analysis of variance results indicated that the layer thickness and raster angle significantly affect the surface roughness of the printed parts, with statistical P-values of 0.016 and 0.039, respectively. This enables an easy selection of the optimal printing parameters to achieve the desired surface roughness. The dimensional accuracy of the fabricated part was also evaluated. Thirteen dimensions of the part features were analyzed, and the results showed that the FDM machine exhibited good accuracy for most of the shapes, with a deviation below 5
Evaluation of lubricant performance in sheet metal forming
Tribology is the science of friction, lubrication and wear which are fundamental elements to all mechanical systems. The importance of savings resulting from oil analysis information reveals hidden information about machine wear condition, lubricant chemistry, or lubricant contamination.
In this webinar, key speakers highlighting 2 main topics:
Evaluation of Lubrication Performance in Sheet Metal Forming, by Dr. Mohd Hafis Sulaiman from TriboMAN IIUM
Gear Coating Experiment, by Dr. Reduan bin Mat Dan from UTe