Table 4.1: parameters used in deep drawing Essay

Table 4.1: Parameters used in deep drawing

Para

meter

Parameter Quantity/ Range

1 Punch Diameter, mm 80

2 Die inner diameter, mm 82.5

3 Blank Holder opening diameter, mm 96

4 Maximum blank Diameter (mm) 180

5 Minimum blank Diameter (mm) 100

6 Blank thickness (mm) 0.9

7 Punch Diameter (mm) 80

8 Die inner Diameter (mm) 82.5

9 Lubrication type MoS2

10 Punch nose radius (mm) 5.5 - 10.5

11 Die shoulder radius (mm) 5.5 - 10.5

12 Blank holder force (kN) 3 - 7

Table 4.2: Optimal parameters obtained through DOE

Process Parameter Level description Level

Punch nose radius, mm 5.5 1

Die shoulder radius, mm 5.5 1

Blank holder force, kN 7 3

The contribution of each highly influencing parameter using ANOVA is shown

in Table 4.3

Table 4.3 Contribution of optimal process parameters found in deep drawing

process

Process parameter Sum of squares S Si % of Contribution description

Punch nose radius, mm 0.505 33.25

Die shoulder radius, mm 0.417 11.52

Blank holder force, kN 0.839 55.23

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Table 4.4 LDR found by traditional experimental method for aluminium at

different temperatures

Material Temperature (oC) LDR

Aluminium

R T 1.8325

100 1.855

150 1.900

200 1.938

Table 4.5 LDR found by traditional experimental method for copper at different

temperatures

Material Temperature (oC) LDR

copper

R T 1.8875

150 1.9563

Table 4.6 LDR found by traditional experimental method for aluminium and

copper at different temperatures

Material Temperature (oC) LDR

Aluminium

R T 1.8325

100 1.855

150 1.900

200 1.938

copper

R T 1.8875

150 1.9563

R T : Room temperature

The optimized process parameters are used for determination of LDR. The LDR

found through traditional method for aluminium and copper at different temperatures are

as shown in Table 4.6.

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4.2 Rapid Determination of LDR

The experimental results revealed that the maximum punch load is linearly

proportional to the blank diameter and this concept is used for rapid nation of LDR. The

LDR calculations have been performed with the use of three deep draw tests. The test

results are used for finding LDR by rapid method of determination for aluminium and

copper different temperatures. Each test consists of two undersize blanks and one over

size blank. The maximum punch load has recorded and plotted on the graph for the

test conducted. The undersize blanks produced a successful cup and over size blank

produced a fractured cup. The oversize blank fractures due to excessive forming load

called critical punch load. The critical blank diameter has found by drawing a horizontal

line passing through the critical punch load (maximum punch load) that intersects with

the line passing through the maximum punch loads of two undersize blanks as shown in

the below Figures. The intersection point gives the maximum size of the blank that can

be successfully drawn without fracture. The Figure 4.1 to 4.7 gives the Critical diameter

for different conditions tested.

Fig. 4.1 Determination of critical diameter for AA6111 aluminum at room

temperature using three data points

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Fig. 4.2: 146.6mm blank successfully drawn and testing the validity of rapid method of finding critical diameter

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Fig. 4.3 Critical diameter for AA6111 aluminum cups drawn at 100oC using

three data points

Fig. 4.4 Determination of critical diameter for aluminium cups drawn at 150oC

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4 RESULTS AND DISCUSSION

4.2 Rapid Determination of LDR

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