Mechanical Testing of Composite Materials
Inserts interfaced with Carbon Fiber Tube
Things to test
Mechanical Tests
Tensile Test- needed for plug
How to test it
Probably not needed since the push rod will be under constant compression
Flexural Test
three-point and four-point bend testing according to ISO 14,125, ISO 178, ASTM D 790, and ASTM D 6272
parameters for this test are the support span, the speed of the loading, and the maximum deflection for the test
Impact Test
Compression Test
End loading
Sheer loading
ASTM D 695, ASTM D 3410, and ISO 14,126.
information on elastic limit, proportional limit, yield point, yield strength, and compressive strength
Strength at high temperatures (Summer)
Fatigue Failure?
Plug Testing
Adhesive
Loctite
EA E-40HT
DP420
DP460
Hysol E‐120HP
Tube and metal prep
Aluminum etching and Alodine coating to prevent corrosion and increase bond strength
West System 860 Aluminum Etching Kit
DuPont Acid Etch and Alodine solutions
Submerge Aluminum in etch solution, then submerge in non-diluted Alodine solution
Aluminum stock for insert
Check for appropriate lengths
Bond length increases linearly with bond strength
Gap 0.004 - 0.012 in for hot bonding
Gap 0.008 in for cold bonding
Carved aluminum, tapped for fitting a bearing insert
create shoulder only for grabbing in tensile test
In MIT paper, flashbreaker tape was used to add thickness at the end of the insert to create equal spacing and center insert.
Process for Insert Tensile Test
Cut CF tube into ~3-5 inch sections
ASTM D 695 (compression test)
What is being recorded: Used to find the modulus of elasticity, yield stress, deformation beyond the yield point, and compressive strength
Procedure: ASTM D695 Rigid Plastic Compression Testing
Machinery Used: Can be performed on either a single-column or dual-column universal testing machine such as those available in Instron's 3400 and 6800 Series (ASTM D695 Compression Testing Rigid Plastics)
ASTM D 3410
What is being recorded: Used to measure the ultimate compressive strain, the compressive modulus of elasticity, Poisson’s ratio, and transition strain.
Machine used: Standard Universal Testing Machine
Procedure: ASTM D3410 Polymer Matrix Composite Shear Load Testing - ADMET (testing procedure tab)
ISO 14,126.
What is being recorded: the compressive strength and compressive modulus of fiber-reinforced plastic composites in the in-plane direction, meaning the direction parallel to the plane of the laminate
Machinery Used: ISO 14126 | ASTM D3410: Shear Loading Compression
Procedure: In-Plane Compressive Properties of Fiber-Reinforced Plastic Composites