Reference no: EM132701223

SEHS4620 Advanced Materials for Design and Technology - The Hong Kong Polytechnic University

Three -point Bending Test of Carbon Fibre Composites

Learning Objective 1: Apply the Rule of Mixtures to predict the Young's modulus of composite materials.
Learning Objective 2: Determine the anisotropic properties of the composite material by varying the orientation of the fibres across four samples.
Learning Objective 3: Be able to conduct three-point bending test and analyse the data generated from the test

Experimental Procedure

1) Measure the dimensions of the sample in length, width, and thickness of Sample 1 in a minimum of 3 separate locations and record the average.
2) Set up the tensile test machine in a reversed pull direction with a jig to enable the samples to be tested under 3-point bending as shown in Figure 1.
3) Load the sample and ensure to remove any backlash (movement in the direction of loading).
4) Zero the load and deflection output and program the rate of loading [1mm/min].
5) Start loading the sample until the deflection is 1mm from starting position and record the load being applied.
6) Repeat the loading in increments of 1mm until 5mm.
7) Repeat Steps 1) to 4) for the remaining 3 composite layup combinations.

1) Using MS Excel, plot P versus wo (from the experimental result) for the four samples on the same graph. Find the least square best fit line for each sample and plot on the same graph.
2) Find the elastic modulus for each sample using Equation 7.
3) Calculate the efficiency (Krenchel) factor using Equation 2 (show your calculations):
4) Use the modified Rule of Mixtures (Equation 2) to predict the elastic modulus of each sample (by part 2)):
5) Compare the elastic moduli calculated by the modified Rule of Mixtures with the values calculated from experimental data (part 2) and part 4)).

Attachment:- Advanced Materials for Design and Technology.rar