Tensile test data for two experimental packaging films, Film A and Film B, are shown in...

 

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Tensile test data for two experimental packaging films, Film A and Film B, are shown in the Excel spreadsheet entitled "Assignment #1 Question 3 tensile test data.xlsx" posted on Courselink. All test films have dimensions of 2 cm width and 5 cm initial length, with a thickness of 50 m thickness. Each of these films are evaluated in the machine and transverse directions (labelled as -1 or 2) to the break point. (i) (ii) Using the spreadsheet provided, calculate the ultimate tensile strength (in MPa), elongation at break (in %), apparent modulus (in MPa) and toughness (in J/m) values for all the four films. Hint: The toughness, which is equivalent to the area under the stress-strain curve, can be estimated using basic geometries or a numerical method (e.g., trapezoidal method) from the data provided. (30%) Which film, A or B, is likely to be uniaxial oriented? Justify your answers. (5%) (iii) Between films A and B, which is tougher, and which is stiffer? Justify your answers. (5%) Force, N 80 80 70 60 60 50 50 40 30 20 20 Vertical (Value) Axis Major Gridlines 10 10 0 0 100 200 300 400 500 Distance, mm Film A-1 -Film A-2 -Film B-1 Film B-2 Tensile test data for two experimental packaging films, Film A and Film B, are shown in the Excel spreadsheet entitled "Assignment #1 Question 3 tensile test data.xlsx" posted on Courselink. All test films have dimensions of 2 cm width and 5 cm initial length, with a thickness of 50 m thickness. Each of these films are evaluated in the machine and transverse directions (labelled as -1 or 2) to the break point. (i) (ii) Using the spreadsheet provided, calculate the ultimate tensile strength (in MPa), elongation at break (in %), apparent modulus (in MPa) and toughness (in J/m) values for all the four films. Hint: The toughness, which is equivalent to the area under the stress-strain curve, can be estimated using basic geometries or a numerical method (e.g., trapezoidal method) from the data provided. (30%) Which film, A or B, is likely to be uniaxial oriented? Justify your answers. (5%) (iii) Between films A and B, which is tougher, and which is stiffer? Justify your answers. (5%) Force, N 80 80 70 60 60 50 50 40 30 20 20 Vertical (Value) Axis Major Gridlines 10 10 0 0 100 200 300 400 500 Distance, mm Film A-1 -Film A-2 -Film B-1 Film B-2