Study on the Impact of Fine-Blanking with Negative Clearance on the Materials Microstructure and Hardness

2010 ◽  
Vol 97-101 ◽  
pp. 149-152
Author(s):  
W.F. Fan ◽  
J.H. Li ◽  
Zhong Mei Zhang
Keyword(s):  
Plastic Deformation ◽  
Research Result ◽  
Original Material ◽  
Fine Blanking ◽  
Complicated Process ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
Negative Clearance ◽  
The Impact ◽  
1045 Steel

The Fine-blanking with negative clearance processing is very complicated process because the blanking clearance is negative clearance, for this reason, the state of stress and strain in sheet inside are also more complicated than conventional blanking. In the process of fine-blanking with negative, plastic deformation of the material is fiercer than conventional blanking, and the change of material inner structure and hardness is more intense because of plastic deformation. The deformation principle of fine-blanking deformation with negative clearance is analyzed by means of streamline and metallographic photograph and micro hardness. The impact of fine-blanking with negative clearance on the materials microstructure and hardness is discussed. The research result indicates that the hardening value is 1.8 times than original material itself and the maximum harden depth is 2.2mm for AISI-1045 steel in the process of blanking with negative clearance. Therefore, it could enhance fatigue strength and the working life of workpiece greatly because of the improvement of the material inner structure.

Study on Microstructure Character in the Deformable Regions of AISI-1045 Steel Fine Blanking with Negative Clearance

2009 ◽  
Vol 628-629 ◽  
pp. 541-546 ◽  
Author(s):  
J.H. Li ◽  
Wei Fu Fan ◽  
Zhong Mei Zhang
Keyword(s):  
Work Piece ◽  
Micro Hardness ◽  
Fine Blanking ◽  
Metallic Crystal ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
Metal Deformation ◽  
Negative Clearance ◽  
1045 Steel ◽  
The Relationship

This paper obtained work piece of fine blanking with negative clearance by experiment. The microstructure and fractography photograph in regions like rollover zone, shearing band, under sheared surface and fracture band were scanned by instrument of scanning electron microscope (SEM-JSM-6360LV). The fine-blanking with negative clearance makes the metal deformation regions into a state of triaxial stress precise and it causes an intense metallic stream that brings about inter-dislocation and distortion of metallic crystal product under the action of stronger force, so the metallic crystal is reset and the isometric metallic crystal of shearing zone is staved, sloped and pulled and it appears as dense lined and strip crystal. The paper analyzes the full course of producing and development of micro crack in the ejecting stage in the fine-blanking processing of negative clearance. And the course of final rupture is also analyzed. The relationship curve of blanking stroke and micro hardness is measured by Vickers Hardness instrument (MH-6). The deforming principle of fine blanking deformation with negative clearance is analyzed by means of microstructure, metallographic photograph and micro hardness.

Comparative Study of the Process Fracture between Fine-Blanking with Negative Clearance and Conventional Blanking

2010 ◽  
Vol 97-101 ◽  
pp. 191-194 ◽  
Author(s):  
Hong Du ◽  
Wei Fu Fan ◽  
Zhong Mei Zhang
Keyword(s):  
Smooth Surface ◽  
Work Piece ◽  
Separation Mechanism ◽  
Final Phase ◽  
Fine Blanking ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
Negative Clearance ◽  
1045 Steel ◽  
Blanking Process

The different separation mechanism of fine-blanking with negative clearance and conventional blanking under different blanking process are analyzed through fine-blanking with negative clearance and conventional blanking processing experiments on AISI-1045 steel. The fractography photographs in the different deformation regions, such as rollover zone, shearing band, fracture zone and burr zone are scanned by scanning electron microscope (SEM-JSM-6360LV). The place of fracture of fine-blanking with negative clearance has emerged into the middle of work piece not the undermost of workpiece, and the width of fracture band is as tiny as 50-100 micron. The smooth surface formed by the uniform plastic flow in the process fine-blanking with negative clearance, and the full course of finally toughness fracture have been analyzed in the final phase of ejecting in fine-blanking with negative clearance. From the perspective of material meso-damage, the fracture mechanism of special blanking process with negative clearance has been illustrated in details.

Study on Working Hardening for AISI-1020 and AISI-1045 Steel Fine-Blanking with Negative Clearance

2010 ◽  
Vol 431-432 ◽  
pp. 405-408 ◽  
Author(s):  
J.H. Li ◽  
Wei Fu Fan ◽  
Zhong Mei Zhang
Keyword(s):  
Work Hardening ◽  
Working Life ◽  
Work Piece ◽  
Micro Hardness ◽  
Fine Blanking ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
Negative Clearance ◽  
1045 Steel ◽  
Vickers Micro Hardness

This paper carries through pure shearing fine-blanking processing experiment with negative clearance for the AISI-1020、AISI-1045 steel and the relations curves of the blanking force and the blanking stroke is obtained. The micro hardness of the sheared surface for the blanked work pieces in breadthways and lengthways direction is measured by Vickers-micro hardness instrument (MH-6), thereby the relations curves of punch stroke and the micro-hardness of the blanking work pieces are gained. The relation between work hardening degree and blanking clearance for the negative blanking is obtained too. This paper focuses on formation mechanism of work hardening for the negative blanking and analyzes the work hardening capability of blanked work piece. The work hardening degree is compared to the materials which possess different hardening index. The research shows that the work hardening degree of the blanking work pieces is strengthened evidently by the fine-blanking with negative clearance and the hardening layer of blanking fracture could enhance structure intensity and wear resistance of blanking work piece evidently. Therefore, it could enhance fatigue strength exceedingly and extend the working life of work piece greatly.

Study on the Optimized Blanking Allowance of Fine-Blanking with Negative Clearance for AISI-1020 and AISI-1045

2010 ◽  
Vol 135 ◽  
pp. 179-183
Author(s):  
Jian Hua Li ◽  
Wei Fu Fan ◽  
Zhong Mei Zhang
Keyword(s):  
Research Result ◽  
Reference Value ◽  
Work Piece ◽  
Key Factors ◽  
Fine Blanking ◽  
Force Increase ◽  
Aisi 1045 ◽  
Negative Clearance ◽  
Deform 2D

The fine-blanking procedure for AISI-1045 and AISI-1020 under the condition of various blanking allowance has been simulated by the DEFORM-2D software, and a large number of fine-blanking experiments have been made. Some key factors, like blanking allowance affecting upon the ejector force, the perfect ratio of fracture and the fracture procedure, are discussed, and the principles for choosing value of blanking allowance are given. In order to reduce ejector force, increase the perfect ratio of fracture and separate scrap from sheet metal easily, a smaller value C of blanking allowance should be adopted whenever possible. The value C of blanking allowance should be chosen according to the mechanism capability. For some types of steels which have good plasticity, a larger value C of blanking allowance should be chosen, so that the work-piece without blanking edge could be obtained. For some types of steels which have poor plasticity, a smaller value C of blanking allowance should be chosen to obtain blanking work-piece with higher quality. Generally speaking, the optimized value of blanking allowance should be from 0.15mm to 0.35mm, and the largest value must be less than 0.5mm.The research result has instructive significance and reference value to improve the quality of work pieces and the perfect ratio of sheared band.

Study on the Process of Pure Shearing and Fracture for AISI-1020 and AISI-1045 Blanking with Negative Clearance

2010 ◽  
Vol 135 ◽  
pp. 215-219
Author(s):  
Wei Fu Fan ◽  
Jian Hua Li ◽  
Zhong Mei Zhang
Keyword(s):  
Experimental Data ◽  
Electron Microscope ◽  
Research Result ◽  
Reference Value ◽  
Work Piece ◽  
Fine Blanking ◽  
Aisi 1045 ◽  
Negative Clearance ◽  
Metallic Sheet ◽  
Scanning Electron

This paper carried through fine-blanking with negative clearance processing experiment with the AISI-1020 and AISI-1045 and obtained the work piece of fine blanking with negative clearance. The fractography photographs in the different deform regions of rollover zone, shearing band, fracture zone and under sheared surface were scanned by scanning electron microscope (SEM-JSM-6360LV). The research result indicates that the plastic flow of fine-blanking with negative clearance has been carried out to punch downspin, then jib at the place of allowance value, so that the length of work piece burnish band as much as possible to maximize and the length of the smooth shearing fracture could reach more than 90% thickness of the metallic sheet. Owing to the ejector negative direction blanking, the second burnish band could be formed in the process of ejecting and the work piece has no burr in the undermost sheared face. The place of fracture of fine-blanking with negative clearance has emerged into the middle of work piece, not into the sheared undermost. And the width of fracture band is very tiny, only 50-100 micron. The research result provides theoretic reference and the experimental data for the practice application. It has instructive significance and reference value to manufacturing application.

Numerical Simulation and Experiment Study on the Blanking Force for AISI-1020 and AISI-1045 Fine-Blanking with Negative Clearance

2011 ◽  
Vol 704-705 ◽  
pp. 1180-1185 ◽  
Author(s):  
J.H. Li ◽  
Zhong Mei Zhang
Keyword(s):  
Numerical Simulation ◽  
Plastic Deformation ◽  
Research Result ◽  
The State ◽  
Metal Sheet ◽  
Experimental Result ◽  
Plastic State ◽  
Element Analysis ◽  
Fine Blanking ◽  
Negative Clearance

Machining experiments of fine-blanking with negative clearance show that the blanking force is very different from ordinary blanking in different blanking stages. Studying on the blanking force size of fine-blanking with negative clearance in different blanking stages is a very important significance for studying die wear and analyzing the state of material stress-strain. Firstly, numerical simulation and stress state analysis of the fine-blanking with negative clearance are carried out, with DEFORM-metal forming finite element analysis software. Afterward the relationship curve of blanking force and stroke are measured, and the blanking force with different blanking stages of fine-blanking with negative clearance is analyzed by the simulation and the experiment. The analysis result shows that the simulation blanking force is bigger than the experimental result (error about 15%), but the blanking force variation tendency is accordant. while the punch pushes down within 0.1mm, the blanking force changes quickly. The metal sheet will enter into the state of plastic deformation after the blanking force reaching maximum value. Along with the punch continues to move down, the area of shear zone is decrescent so that the blanking force inches down, and the blanking force reaches a certain value in the place of blanking allowance value finally. With punch pushing the metal sheet to enter the plastic state and punch downward the place of the allowance value, the metal sheet sustained the big blanking force all the time as well as the deformation zone material keeps the plastic deformation. The research result provides theoretic reference and the experimental data for the practice application of fine-blanking with negative clearance, and has instructive significance and reference value to mould design.

Evolution of Dynamic Recrystallization of AISI-1045 Steel under Critical Friction Conditions

2014 ◽  
Vol 966-967 ◽  
pp. 168-174
Author(s):  
Kevin Le Mercier ◽  
Michel Watremez ◽  
Julien Brocail ◽  
Laurent Dubar
Keyword(s):  
Dynamic Recrystallization ◽  
Volume Fraction ◽  
Work Piece ◽  
Arbitrary Lagrangian Eulerian ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
Sliding Test ◽  
The Impact ◽  
1045 Steel ◽  
Frictional Behaviour

To determine the impact of dynamic recrystallization on frictional behaviour in the tool-chip interface, a specific friction test called the Warm and Hot Upsetting Sliding Test (WHUST) is implemented. This friction bench simulates tests with contact pressure, sliding velocity, contactor and specimen temperatures similar to industrial ones. Several tests are performed on specimens at different sliding speed, penetrations and work-piece temperatures to reach different dynamically recrystallized states. A numerical model of this test using Arbitrary Lagrangian Eulerian (ALE) method is implemented. Thanks to a specific rheological model, we are able to predict the evolution of the volume fraction of recrystallized grains.

Fuzzy Modeling to Simulate Surface Roughness in CNC Turning of AISI 1045 Steel

2011 ◽  
Vol 486 ◽  
pp. 262-265
Author(s):  
Amit Kohli ◽  
Mudit Sood ◽  
Anhad Singh Chawla
Keyword(s):  
Experimental Data ◽  
Surface Roughness ◽  
Process Parameters ◽  
Fuzzy Model ◽  
Fuzzy Modeling ◽  
Cnc Machine ◽  
Model Based ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
1045 Steel

The objective of the present work is to simulate surface roughness in Computer Numerical Controlled (CNC) machine by Fuzzy Modeling of AISI 1045 Steel. To develop the fuzzy model; cutting depth, feed rate and speed are taken as input process parameters. The predicted results are compared with reliable set of experimental data for the validation of fuzzy model. Based upon reliable set of experimental data by Response Surface Methodology twenty fuzzy controlled rules using triangular membership function are constructed. By intelligent model based design and control of CNC process parameters, we can enhance the product quality, decrease the product cost and maintain the competitive position of steel.

scholarly journals Evaluation of the characteristics of an AISI 1045 steel quenched in different concentration of polymer solutions of polyvinylpyrrolidone

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Eduardo da Rosa Vieira ◽  
Luciano Volcanoglo Biehl ◽  
Jorge Luis Braz Medeiros ◽  
Vagner Machado Costa ◽  
Rodrigo Jorge Macedo
Keyword(s):  
Microstructural Characterization ◽  
Exchange Capacity ◽  
X Ray Diffraction ◽  
Thermal Exchange ◽  
The Core ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
Quench Hardening ◽  
Polymeric Solutions ◽  
1045 Steel

AbstractQuench hardening aims at the microstructural transformation of steels in order to improve hardness and mechanical strength. The aim phase is, in most cases, the martensite. It is necessary to heat the material until it obtains its austenitization and quenching by immersion in a fluid. Currently, it is common to use watery polymeric solutions in this procedure. These fluids, which are the mixture of polymers in water, vary their thermal exchange capacity depending on the concentrations applied. The increase in concentration minimizes the removal of heat from the part, reducing the formation capacity of martensite, and developing a lower hardness and strong steel. In this work, microstructural characteristics and properties of AISI 1045 steel quenched in solutions based on polyvinylpyrrolidone (PVP) in 10, 15, 20, and 25% concentration were evaluated. The microstructural characterization quantified the percentage of the phases in each concentration, demonstrating a reduction of martensite as the concentrations were high. The investigation of the samples by x-ray diffraction confirmed the absence of austenite retained in the material. Furthermore, a microhardness scale between the core and the surface was constructed, in which a reduction gradient of the indices of this property towards the core of the sample was evidenced.

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