Tensile Test Dr. Ken Lulay EGR270 Materials Laboratory Spring 2014

Tensile Test Dr. Ken Lulay EGR270 Materials Laboratory Spring 2014

Overview Tensile testing review Test procedure Materials to be tested

Tensile Testing Uniaxial test (load in one direction) Record force ( F/A0) and strain Important mechanical properties Yield strength ( ys or yp) Tensile strength ( UT) Modulus of Elasticity (E) Ductility (%EL and %RA)

Test Standard ASTM E8 – Standard Test Methods of Tension Testing of Metallic Materials Gage length 4D (uniform stress) Grips should be free to rotate uses spherical bearing to allow rotation creates a 2-force member (axial load) Temperature between 50 and 100 F

Procedure Mark, measure and record: gage length (close to 2 inches) diameter Load into test frame (SATEC) Apply load, record force and strain After fracture, measure and record: final gage length diameter in necked region

Materials to be Tested 2024-T351 aluminum alloy AISI 1045HR (hot rolled) UHMW-PE (polyethylene) Acrylic Already tested: 1018CF, 1045CF, 4140CF

Aluminum Alloys Designation of wrought aluminum alloys (by the Aluminum Association) – the first digit of the four digit scheme indicates primary alloying elements:

Heat Treatable Wrought aluminum alloys 2xxx – copper 4xxx – silicon 6xxx – magnesium and silicon 7xxx – zinc 8xxx – other elements

Non-Heat Treatable wrought aluminum alloys 1xxx – commercially pure aluminum 3xxx – manganese 5xxx – magnesium

Cast aluminum alloys 1xx.x – 99.00% pure aluminum 2xx.x – copper 3xx.x – silicon with copper and/or magnesium 4xx.x – silicon 5xx.x – magnesium 7xx.x – zinc 8xx.x – tin 9xx.x – other elements

Temper Designation F: As fabricated O: Annealed W: Solution heat-treated. H: Strain hardened. T: Thermally treated.

T1 – Cooled from hot working temperature and naturally aged T2 – Cooled from hot working temperature, cold worked, naturally aged T3 – Solution heat treated, cold worked, naturally aged T4 – Solution HT, naturally aged T5 – Cooled from elevated temperature and artificially aged T6 – Solution HT, artificially aged. T7 – Solution heat treated and overaged or stabilized (corrosion resistance).

2024-T351 2xxx copper main alloy element 2024: 4.4%Cu, 1.5%Mg, 0.6%Mn T: Thermally treated T3: sol’n HT, cold worked, nat. aged T351: sol’n HT, cold worked for stress relief, natural aged.

UHMW-PE Ultra-High Molecular Weight, Polyethylene Thermoplastic Thermoplastics are strain rate sensitive Ultra-High Molecular Weight? Stiffness Strength Thermoplastics are temperature sensitive

Acrylic (Polymethylacrylate)

Any questions Tensile testing? Stress-strain curves? What we are doing today? What is required?