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ASTM Testing Standards

ASTM C393_Standard Test Method for Shear Strength

 Test Specimen Sampling and Geometry
  • Specimen is rectangular in cross-section

  • Length x Width x Depth - 200 mm x 75 mm x Thickness of Sandwich Construction

  • Make sure to test at least five specimens per test condition unless you are confident that the results obtained are valid through the use of fewer specimens.

 Equipment and Apparatus:
  • Apparatus: UTM with a deflection transducer, pictured below

 Procedure:

  • Condition the specimen in a chamber if the test environment is not the same as a conditioned environment.

  • Measure the length, width and thickness at three places in the specimen.

  • Place the specimen into the test fixture as shown in the equipment and apparatus section.

  • Attach the deflection transducer.

  • Apply a compressive force to the specimen until failure or until a deflection equal to the thickness is reached.

  • Speed of Testing = 6mm/min

  • Failure should occur at 3-6 minutes.

 Basic Description:
  • 3-point or 4-point bend test

 Reported during the test:
  • Force versus crosshead displacement, force versus deflection data continuously, or at frequent intervals (around 2-3 recordings per second, with a target minimum of 100 recorded data points)

  • If there are any initial failures, record force, displacement and mode of damage where the failure occurs. 

  • Record mode, area and location of each failure. 

  • Use the failure identification codes

  • Record the max force, failure force, head displacement and the deflection at the moment of ultimate failure. 

  • For ultimate failure modes, record the mode, area and location of ultimate failure for each material. 

  • Calculations:

    • For 3-Point Mid-Span Loading:

    • For 4-Point, Quarter-point loading:

    • For 4-Point (Third Point) Loading:

ASTM D3039_Standard Test Methods for Tensile Properties

 Test Specimen Sampling and Geometry
 Equipment and Apparatus:
  • 3 Force Indicator, Grips, Strain-Indicating Device, Strain transducer, Extensometer, Strain Gauge, End Tabs. 

  • Tensile Testing machine with a stationary head and a movable head. 

 Procedure:
  • Test at least 5 specimens

  • Measure the specimen in 3 places and report average thickness and width as well as average area. 

  • The speed of testing should be able to have a nearly constant strain rate and it will produce failure within 1 to 10 min. 

 Basic Description:
  • Tensile Test

 Reported during test:
  • Calculate modulus of elasticity

  • Calculate ultimate tensile strength. 

  • If tensile modulus/ultimate tensile strain will be calculated, get the tensile strain at the indicated displacement at each required data point. 

  • Tensile chord modulus of elasticity.

  • Poisson’s Ratio by Chord Method.

*All these equations are found in the confluence page*

 ASTM D3410_Standard Test Method for Compressive Properties of Polymer Matric Composite Materials

 Test Specimen Sampling and Geometry
  • Sampling—Test at least five specimens per test condition unless valid results can be gained through the use of fewer specimens

  • The test specimen will have a constant rectangular cross section with a specimen width variation of no more than 1% and a specimen thickness variation of no more than 2%, the tables below give more detail.

  • Below is an equation to get the recommended test thickness

 Equipment and Apparatus:
  • Equipment required:

    • Micrometers/calipers

    • Strain-Indicating Device

    • Bonded Resistance Strain Gauges

    • Emery cloth

    • Special Alignment Jig (pictured below)

  • Compression Testing Fixture(pictured below are schematics and the actual fixture)

  • Apparatus:

    • There will be a force indicator

    • The machine will have two loading heads. 

^^^I don’t exactly know what this means (interpret pls)

  • The drive mechanism will be able to give a controlled displacement rate with respect to the stationary head. 

  • If the atmosphere conditions suck use a conditioning chamber and an environmental test chamber.

  • If the material is super stiff use an extensometer. 

 Procedure:
  • Test at least five specimens per test condition

  • Get ready because this is a HEFTYYY procedure 

  • General instructions:

    • Condition specimens before/after strain gaging as required. Condition travelers if they will be used

    • Apply strain gages/extensometers to both faces of the specimen

    • The loading rate should produce a failure within 1 to 10 min. 

      • Strain-Controlled Tests, standard strain rate of 0.01 min/1 ?? I think the unit may be wrong here. I think it's supposed to be mm/min??

      • Constant Head-Speed Tests, A standard crosshead displacement of 1.5mm.min. 

    • Monitor test temp by placing a thermocouple within 25mm of the specimen gauge section. You can also tape the thermocouple(s) to the test specimen and travelers. 

  • Fixture Installation:

    • Place the lower wedge housing block on the lower platen, then attack the upper wedge housing block to the upper crosshead/insert it into the upper wedge housing holding fixture, centered over the lower wedge housing block. 

    • Move a crosshead to close the distance between the 2 housing blocks while guiding the bearing guide rods into the mating bearing of the companion housing block. The lower housing block can be fitted with guide rods long enough to allow the rods to remain in the bearings while the wedges or specimen assembly is loading into and out of the housing blocks. 

  • Specimen Insertion:

    • If needed, move the testing machine crosshead to open the distance between the 2 housing blocks so both the upper and lower wedge rip assemblies may be accessed. 

    • I’m so sorry but idk how to summarize the following thing :(

  • If the specimen will be aligned with the wedge grips in the fixture housing block, the lower jaws should be raised so that grip-faces open to allow specimen insertion.

  • If we need to, free the upper wedge grips so they are in the fully open position. Moving the crosshead, close the distance between the housing blocks and guide the upper end of the specimen into the opening between the upper wedge grips. 

  • Close the upper grips manually to check the specimens vertical displacement. Do it with the lower grips as well. The upper grips should be in full contact with the wedge when closed. Repeat if we need to. 

  • Keep the grips closed and slowly close the distance between the housing blocks by moving the crosshead, watch the force indicator at this time. Stop the crosshead when the specimen begins to take a compressive force. 

  • Transducer Installation:

    • If the strain-transducer(s) other than strain gages will be used, attach them to the specimen at the mid-span, mid-width location. Then, attach the strain recording instrumentation to the strain gages or other transducers on the specimen. Then, remove any remaining preload and zero the transducer(s).

  • Loading:

    • Apply the force to the fixture at the specified rate until failure while recording data.

 Basic Description:
 Reported during test:
  • Failure modes:

    • Record them by giving a code as shown below:


  • There are a few unacceptable failure modes including end-crushing and euler buckling. 

  • Calculations:

    • Compressive Stress/Ultimate Compressive Stress.

    • Compressive Strain and Ultimate Compression Strain. 

    • Compressive Modulus of Elasticity

    • Compressive Poisson’s Ratio

    • Transition Strain

  • The following should be noted:

    • Ultimate compressive strength

    • Ultimate compressive strain

    • Compressive (linear or chord) modulus of elasticity

    • Poisson’s ratio in compression

    • Transition strain

*remember all these formulas will be in the astm document for finding the above values*

ASTM D3518_Standard Test Method for In-Plane Shear Response of Polymer Matrix Composite Materials by Tensile Test

 Test Specimen Sampling and Geometry
  • Will be the same as the above standard along with the following:

 Equipment and Apparatus:
  • Same as ASTM D3039

 Procedure:
  • Test at least five specimens per test condition

  • Same as ASTM D3039 as well as:

    • This test will have normal strain instrumentation in both the longitudinal and transverse directions. It will also have a continuous/nearly continuous force normal strain data recording. 

 Basic Description:
  • Same as ASTM D3039.

 Reported during test:
  • Calculations:

    • Max shear stress/shear stress

    • Shear strain/max shear strain

    • Shear modulus of Elasticity

    • Offset Shear Strength

    • Various statistics


*Again, all these formulas will be in the confluence page*

ASTM D903_Standard Test Method for Peel or Stripping Strength of Adhesive Bonds

 Test Specimen Sampling and Geometry
  •   The above is the diagram of the geometry

  • Test at least 10 test specimens for each adhesive.

  • Discard specimens that give out of line test results due to obvious flaws and then retest.

 Equipment and Apparatus:
  • Apart from the testing apparatus, the only equipment needed is a conditioning room/desiccators

  • The following is a picture of the testing apparatus:

 Procedure:
  • Hehe…remember this…yeah it still makes no sense :C

 Basic Description:
  • Ummm...help

 Reported during test:
  • These are the only values needed to be reported (they don’t seem like they’re calculations)

    • Average peel/stripping strength.

    • Max and Min strength values of the series.

    • Type of failure.

ASTM D905_Standard Test Method for Strength Properties of Adhesive Bonds in Shear by Compression Loading (for adhesives on wood)

 Test Specimen Sampling and Geometry:
  • Will conform to the following geometry:

  • At least 20 specimens shall be tested, representing at least four different joints

 Equipment and Apparatus:
  • No equipment listed, just apparatus:

    • The machine will have a capacity of no less than 6810kg in compression and shall be fitted with a shearing tool containing a self-aligning seat to ensure uniform lateral distribution of the load.

    • It will be able to maintain a uniform rate of loading so the load may be applied with a continuous motion. The apparatus is pictured below:

 Procedure:
  • At least 20 specimens should be tested, they will represent at least four different joints.

  • We will have to prep the test joints:

    • They will be hard maple blocks, having a minimum specific gravity of 0.65 based on oven-dry weight and volume shall be selected. Below is a picture of the test joints and how they should be cut?

 Basic Description:
  • I don’t really get how to explain this one to be honest help :C

 Reported during test:
  • Calculations:

    • Shear stress at failure.

    • Max and min shear stress at failure and percentages of wood failure.

    • The standard deviation of all individual test values.

    • Average shear stress at failure and the average percentage of wood failure.

ASTM D950_Standard Test Method for Impact Strength of Adhesive Bonds

 Test Specimen Sampling and Geometry:
  • Use these if you can:

  • Test 10 test specimens for each adhesive

 Equipment and Apparatus:
  • Equipment:

    • Desiccators

    • Conditioning chambers

  • Apparatus:

    • Use a pendulum-type impact machine (pictured below).

  • Use a jig to hold the specimen as shown below.

  • Use a vise/bolts to hold the jig rigid.

 Procedure:
  • Put the specimen in the jig in the vise of the machine so the specimen butts squarely against the end of the jig.

  • Rest the impact head against the specimen and adjust the jig so the head fits squarely against the impact face.

  • Raise the impact head and release the safety catch.

  • We will then note the impact energy absorbed.

 Basic Description:
  • A pendulum will fall and hit our specimen and test the adhesive strength

 Reported during test:
  • Joules of energy absorbed in producing failure of the specimen

  • Percentages of cohesion, adhesion, and contact failure. This will be based on visual inspection. 

  • Calculation:

    • Impact strength of the specimen over the bonded area. 


*the calculations will be available in the confluence page*

ASTM D5868_Standard Test Method for Lap Shear Adhesion for Fiber Reinforced Plastic (FRP) Bonding

 Geometry:
  • Substrates—Fiber reinforced plastic (FRP) as specified, with metal composition (heat treat, temper, and condition) and roughness as specified when bonding FRP to metal. (I don’t know what this means)

  • Cut fiber-reinforced plastic parts into flat coupons 1 by 4 in. (25.4 by 100 mm) at a nominal thickness of 0.1 in. (2.5 mm). In the case of FRP-to-metal bonding, use metal with a nominal thickness of 0.06 in. (1.5 mm). It is recommended that a diamond tip water-cooled saw blade be used, or a cutting method capable of producing sharp cut edges.

  • Joint Geometry—Control joint geometry by appropriate fixturing, using glass beads or other suitable means to control a 0.03-in. (0.76-mm) adhesive bondline thickness. Use the minimum number of glass beads in the glue line needed to hold bondline thickness. Fixturing pressure is allowed. Lap shear overlap will be 1 by 1 in. (25.4 by 25.4 mm) See Figure 1 below.

  • Prepare a minimum of 5 lap shear samples in each case and test.

 Equipment and Apparatus:
  • No equipment is outlined, only an apparatus which is said to most likely just be a simple tensile tester like pictured below

 Procedure:
  • Prepare a minimum of 5 lap shear samples in each case and test.

  • Prep the surface of the FRP as recommended by the adhesive manufacturer. If there is no recommendation, prep the surface as outlined in practice D2093

  • Apply the adhesive in accordance with the adhesive suppliers recommendations. 

  • Adhesive Cure—Cure the adhesive at room temperature or elevated temperature using prescribed conditions determined by the adhesive supplier.

  • The initial grip separation is 75mm, with a minimum of 25.4mm of each sample end held in the test grips.

  • The load rate is 13mm/min. 

  • This load rate is said to be an important difference compared to other standards. 

 Basic Description:
  • Tensile test.

 Reported during test:
  • Complete identification of the adhesive tested, this includes the type and manufacturers code number. 

  • Complete identification of the substrates used. This includes the type of resin and fiber orientation as well as the method of surface prep prior to bonding.

  • Cure schedule time and temperature for bonding sample. 

  • Individual peak load values, and averages by maximum and minimum values.

  • Test temperature and conditions.

  • Type of failure whether it be fiber tear, cohesive, adhesive.

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