Effect of experimental conditions on nano-indentation response of low density polyethylene (LDPE)

Figures & data

Figure 1. Indentation load as a function of displacement for different amplitudes (1, 5, 10 nm).

Figure 2. Hardness as a function of displacement for different amplitudes (1, 5, 10 nm).

Figure 3. Modulus as a function of displacement for different amplitudes (1, 5, 10 nm).

Figure 4. Indentation Load as a function of displacement for different frequencies (11.2, 22.5, 45 Hz).

Figure 5. Hardness as a function of displacement for different frequencies (11.2, 22.5, 45 Hz).

Figure 6. Modulus as a function of displacement for different frequencies (11.2, 22.5, 45 Hz).

Figure 7. Indentation load as a function of displacement for different strain rates (0.02, 0.05, 0.1, 0.2, 1 s⁻¹).

Figure 8. Creep displacement as a function of strain rate at a constant frequency of 45 Hz and an amplitude of 2 nm.

Figure 9. Hardness as a function of displacement for different strain rates (0.02, 0.05, 0.1, 0.2, 1 s⁻¹).

Figure 10. Modulus as a function of displacement for different strain rates (0.02, 0.05, 0.1, 0.2, 1 s⁻¹).

Figure 11. Indentation load as a function of displacement by having peak load of 10 mN for different holding times (1, 3, 5, 10, 20, 50, 100 sec).

Figure 12. Indentation load as a function of displacement by having peak load of 30 mN for different holding times (1, 3, 5, 10, 20, 50, 100 sec).

Figure 13. Indentation load as a function of displacement by having peak load of 100 mN for different holding times (1, 3, 5, 10, 20, 50, 100 sec).

Figure 14. Creep displacement as a function of holding time for different peak loads (10, 30, 100 mN). The solid line represents model fitting.

Table 1. Values of fitting parameters for Eq. [1][1] $$\Delta h=A·\ln (B·t+1)$$[1] .

Sr. #	Load (mN)	Parameter A (nm)	Parameter B (sec^-1)	r^2
1	10	443	0.16	0.99
2	30	827	0.13	0.98
3	100	1830	0.10	0.97

Figure 15. Hardness as a function of holding time for different peak loads (10, 30, 100 mN). Bars represent standard deviation.

Figure 16. Modulus as a function of holding time for different peak loads (10, 30, 100 mN). Bars represent standard deviation.

Table 2. Recommended holding times for LDPE with different peak loads.

Sr. #	Load (mN)	Recommended Holding Time (sec)
1	10	655.0
2	30	693.0
3	100	804.5

Figure 17. Creep rate as a function of holding time for different peak loads (10, 30, 100 mN).