I conducted tension tests on two materials; a 3d printed abs beam and a plastic buckle with textile straps.
3d printed abs beam
Sam helped me to cut the abs part out with a hand saw.
Measured the dimension: Area = 18.09mm * 4.56mm; L = 20.61mm.
Here is the result. Blue indicates the stress-strain curve; Red is the trend line of the linear part which is relevant to the elastic modulus.
I stopped the testing due to the deformation at the clamped area.
Following the formula, the Young’s modulus for this object is calculated as: E = (2000N/(18.09mm*4.56mm))/((1.2mm-0.3mm)/20.61mm) = 555.22[N/mm^2] = 555.22[MPa] = 0.56 [GPa].
It is almost one-third of the Young’s Modulus of ordinary ABS plastics.
There observed some stress and deformation left on the material.
I cut this buckle piece out from a neck strap.
The object consists of the strap parts (textile) and the buckle part (plastic) between them.
Here is the result. Blue indicates the relationship between load and extension; Red is the trend line of the linear part.
383.44 N (39.13 Kg) was the maximum load before it broke.
Red circle indicates some slack was resolved then. I observed enough tension on the straps and the buckle parts after 10mm and onwards till it was broken.
The connection between the strap and the buckle was broken.
The Graduate (1967)