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Mixed-Mode I/II

The problems associated with Mode I and Mode II loading configurations, such as inelastic material behaviour, large displacement effects, frictional forces in the form of abrasion between upper and lower fracture surfaces are just as pertinent, if not more so, to mixed-mode configurations. The work on the following test geometries can be considered still in its infancy, despite the claims of their authors. Further research into measurement techniques for monitoring the onset and progress of delamination and methods of pre-cracking is required.

Mixed-Mode Bend (MMB): This test consists of clamping one end of a DCB specimen and applying load to one of the adherends. By using adherends of different bending stiffness (i.e. altering the thickness ratio of the two adherends) the ratio of G_I/G_II can be varied. Test specimen dimensions and fabrication are similar to those used for DCB and ENF specimens. A special fixture is required.

Crack Lap Shear (CLS): This method enables the magnitude of the shear and peel stress components to be varied, by changing the relative thickness of strap and lap adherends. Load is applied axially. Failure is Mode II dominated with G_I/G_II ratios ranging from 20 to 35% [6]. The specimen can be loaded in either tension or flexure (four-point bend). Mode I component increases when the CLS specimen is subjected to pure bending, also the energy release rate is independent of crack length.

References

• ISO 3167: 1993, “Plastics—Multipurpose Test Specimens.”
• ISO 527–1: 1993, “Plastics—Determination of Tensile Properties—Part 1: General Principles.”
• ASTM D 897–01, “Standard Test Method for Tensile Properties of Adhesive Bonds,” ASTM Standards Volume 15.06.
• ASTM D 2095–96 (2002), “Standard Test Method for Tensile Strength of Adhesives by Means of Bar and Rod Specimens,” ASTM Standards Volume 15.06.
• BS EN 26922: 1993, “Adhesives—Determination of Bond Strength in Direct Tension.”
• “Adhesives and Sealants,” Engineered Materials Handbook, Volume 3, ASM International, 1990.
• Harris, A.J. and Adams, R.D., “An Assessment of the Impact Performance of Bonded Joints in Use in High Energy Absorbing Structures,” Proceedings of the Institute of Mechanical Engineering, 199 (C2), 1985, pp 121–131.
• Saunders, D.E.J., “A Critical Review of Test Methods for Adhesively Bonded Joints,” unofficial NPL Report, January 1992.
• ISO 8510–2: 1990, “Adhesives—Peel Test for a Flexible-Bonded-to-Rigid Test Specimen Assembly—Part 2: 180 Degree Peel.”
• ISO 11339: 2003, “Adhesives—T-Peel for Flexible-to-Flexible Bonded Assemblies.”
• ASTM D 1876–01, “Standard Test Method for Peel Resistance of Adhesives (T-Peel Test),” ASTM Standards, Volume 15.06.
• “Experimental Assessment of Durability of Test Methods,” MTS Adhesive Programme, Project 3: Environmental Durability of Adhesive Bonds, Report No 8, AEA Technology, Harwell, United Kingdom, January 1995.
• Sheasby, P.G., Gao, Y. and Wilson, I., “The Robustness of Weld-Bonding Technology in Aluminium Vehicle Manufacturing,” SAE Technical Paper 960165, 1996.
• BS 5350 Part C13: 1990, “Methods of Test for Adhesives. Adhesively Bonded Joints: Mechanical Tests. Climbing Drum Peel Test.”
• ASTM D 1781–98, “Standard Test Method for Climbing Drum Peel for Adhesives,” ASTM Standards Volume 15.06.
• ASTM D 3167–97, “Standard Test Method for Floating Roller Peel Resistance of Adhesives,” ASTM Standards Volume 15.06.
• ISO 4578: 1997, “Adhesives—Determination of Peel Resistance of High-Strength Adhesive Bonds—Floating Roller Method.”
• ASTM D 3762–98, “Standard Test Method for Adhesive-Bonded Surface Durability of Aluminium (Wedge Test),” ASTM Standards Volume 15.06.
• “Adhesive Bonding Handbook for Advanced Structural Materials,” European Space Research and Technology Centre, European Space Agency, Noordwjik, The Netherlands, 1990.
• Stone, M.H., “The Effect of Silane Coupling Agents on the Durability of Titanium Alloy Joints,” Journal of Adhesion, 26, 1988, pp 101–111.
• BS 5350 Part C1: 1990, “Methods of Test for Adhesives. Adhesively Bonded Joints: Mechanical Tests. Climbing Drum Peel Test.”
• ASTM D 1062–02, “Standard Test Method for Cleavage Strength of Metal-to-Metal Adhesive Bonds,” ASTM Standards Volume 15.06.
• BS EN 1465: 1995, “Adhesives—Determination of Tensile Lap-Shear Strength of Rigid-to-Rigid Bonded Assemblies.”
• ASTM D 1002–01, “Standard Test Method for Apparent Shear Strength of Single-Lap Joint Adhesively Bonded Metal Specimens by Tension Loading (Metal-to-Metal),” ASTM Standards Volume 15.06.
• BS 5350—Part C5: 1990, “Adhesives—Determination of Bond Strength in Longitudinal Shear.”
• Adams, R.D. and Harris, J.A., “The Influence of Local Geometry on the Strength of Adhesive Joints,” International Journal of adhesion and Adhesives, 7(2), 1987, pp 69–80.
• ISO 9664: 1995, “Adhesives—Test Methods for Fatigue Properties of Structural Adhesives in Tensile Shear.”
• ASTM D 3166–99, “Standard Test Method for Fatigue Properties of Adhesives in Shear by Tension Loading (Metal/Metal),” ASTM Standards Volume 15.06.
• ASTM D 3528–96 (2002), “Standard Test Method for Strength Properties of Double-Lap Shear Adhesive Joints by Tension Loading,” ASTM Standards Volume 15.06.
• Fay, P.A. and Maddison, A., “Durability of Adhesively Bonded Steel under Salt Spray and Hydrothermal Stress Conditions,” International Journal of Adhesion and Adhesives, 10(3), 1990, pp 179–186.
• Iosipescu N., “New Accurate Procedure for Single Shear Testing of Metals,” Journal of Materials, 2(3), 1967, pp 537–566.
• Walrath, D.E. and Adams, D.F., “The Iosipescu Shear Test as Applied to Composite Mechanics,” Experimental Mechanics, 23(1), 1983, pp 105–110.
• ASTM D 5379/5379M-98: “Standard Test Method for Shear Properties of Composite Materials by the V-Notched Beam Method,” ASTM Standards Volume 15.03.
• Duncan, b.c. and Dean G.D., “Test Methods for Determining Shear Property Data for Adhesives Suitable for Design. Part A: Summary,” MTS Adhesive Programme, Project 1: Basic Mechanical Properties for Design, NPL Report CMMT(B)55, June 1996.
• Duncan, b.c. and Dean G.D., “Test Methods for Determining Shear Property Data for Adhesives Suitable for Design. Part B: Full Results,” MTS Adhesive Programme, Project 1: Basic Mechanical Properties for Design, NPL Report CMMT(B)56, April 1996.
• Grabovac, I. and Morris, c.e.M., “The Application of the Iosipescu Shear Test to Structural Adhesives,” Journal of Applied Polymer Science, 33, 1991, pp2033–2042.
• Wycherley, G.W., Mestan, S.A. and Grabovas, I., “A Method for Uniform Shear Stress-Strain Analysis of Adhesives,” Journal of Testing and Evaluation, 18(3), 1990, pp 203–209.
• Broughton, W.R., Gower, M.R.L., Lodeiro, M.J. and Shaw, R.M., “Through-Thickness Testing of Polymer Matrix Composites,” NPL Measurement Note MATC(MN)06, 2001.
• Arcan, M., Hashin, Z. and Voloshin., “A Method to Produce Uniform Plane-Stress States with Applications to Fibre Reinforced Materials,” Experimental Mechanics, 18 (4), 1978, pp 141–146.
• Banks-Sills, L. and Arcan, M., “A Compact Mode II Fracture Specimen,” Fracture Mechanics: 17th Volume, ASTM STP 905, American Society for Testing and Materials, Philadelphia, Pennsylvania, USA, 1986, pp 347–363.
• Voloshin, A. and Arcan, M., “Pure Shear Moduli of Unidirectional Fibre Reinforced Materials,” Fibre Science and Technology, 13, 1980, pp 125–134.
• Weissberg, V. and Arcan, M., “A Uniform Pure Shear Testing Specimen for Adhesive Characterisation,” Adhesively Bonded Joints: Testing, Analysis and Design,” ASTM STP 981, W.S. Johnson, Editor, American Society for Testing and Materials, Philadelphia, Pennsylvania, USA, 1988, pp 28–38.
• Marloff, R.H., “Finite Element Analysis of Biaxial Stress Test Specimen for Graphite/Epoxy and Glass Fabric/Epoxy Composites,” Composites Materials: Testing and Design (Sixth Conference), ASTM STP 787, I.M. Daniel, Editor, American Society for Testing and Materials, Philadelphia, Pennsylvania, USA, 1982, pp 34–49.
• ASTM D 3044–04 (2000), “Standard Test Method for Shear Modulus of Wood-Based Structural Panels,” Volume 4.10, ASTM Standards Volume 4.10.
• ISO 15310: 1999, “Fibre-Reinforced Plastic Composites—Determination of In-Plane Shear Modulus by the Plate Twist Method.”
• Sims, G.D., Nimmo, W., Johnson, A.F. and Ferriss, D.H., “Analysis of Plate-Twist Test for In-Plane Shear Modulus of Composite Materials,” NPL Report DMM(A)54, 1992.
• Gommers, B., Verpoest, I. and Van Houtte, P., “Further Developments in Testing and Analysis of the Plate twist Test for In-Plane Shear Modulus Measurements,” Composites Part A, 27A, 1996, pp 1085–1087.
• Dean G.D., Duncan, b.c., Adams, R., Thomas, R. and Vaughn, L., “Comparison of Bulk and Joint Specimen Tests for Determining the Shear Properties of Adhesives,” MTS Adhesive Programme, Project 1: Basic Mechanical Properties for Design, NPL Report CMMT(B)51, April 1996.
• Thomas, R. and Adams, R., “Test Methods for Determining Shear Property Data for Adhesives Suitable for Design Part 2: The Torsion Method for Bulk and Joint Specimens,” NPL Report CMMT(B)56, 1996.
• Nadai, A., “Plasticity. A Mechanics of the Plastic State of Matter,” McGraw-Hill, New York, 1931, pp128–130.
• Vaughan, L.F. and Adams R.D., “Test Methods for Determining Shear Property Data for Adhesives Suitable for Design. Part 3: The Thick Adherend Test,” MTS Adhesive Programme Project 1, Report No 8, March 1996.
• ISO 11003–2: 1994, “Structural Adhesives—Determination of Shear Behaviour—Part 2: Thick Adherend Tensile-Test Method.
• ASTM D 3165–00, “Standard Test Method for Strength Properties in Shear by Tension Loading of Single-Lap-Joint Laminated Assemblies,” ASTM Standards Volume 15.06.
• ASTM D 695–02a, “Standard Test Method for Compressive Properties of Rigid Plastics,” ASTM Standards Volume 8.01.
• Broughton, W.R. and Mera, R.D., “Environmental Degradation of Adhesive Joints Accelerated Testing,” NPL Report MATC(A)197, 1999.
• Mera, R.D. and Sims, G.D., “Round-Robin Validation Exercise for the Thick Adherend Shear Test in Compression,” NPL Measurement Note MATC(MN)46, 2003.
• Kinloch, A.J., “Adhesion and Adhesives—Science and Technology,” Chapman and Hall, 1987.
• ASTM D 3433–99, “Standard Test Method for Fracture Strength in Cleavage of Adhesives in Bonded Metal Joints,” ASTM Standards Volume 15.06.
• BS 7991: 2001, “Determination of the Mode I Adhesive Fracture Energy G_IC of Structure Adhesives Using the Double Cantilever Beam (DBC) and Tapered Double Cantilever Beam (TDCB) Specimens.”
• Williams, J.G., “Large Displacement and End Block Effects in the ‘DCB’ Interlaminar Test in Modes I and II,” Journal of Composite Materials, 21, 1987, pp 330–347.
• Kinloch, A.J. and Osiyemi, S.O., “Predicting Fatigue Life of Adhesively-Bonded Joints,” Journal of Adhesion, Volume 43, 1993, pp 79–90.
• Fernlund, G., Papini, M., McCammond, D. and Spelt, J.K., “Fracture Load Predictions for Adhesive Joints,” Composites Science and Technology, Volume 51, 1994, pp 587–600.
• Ashcroft, I.A, Gilmore, R.B and Shaw, S.J., “Cyclic Fatigue and Environmental Effects with Adhesively Bonded Joints,” AGARD 83^rd SMP Meeting, Florence, 1996.
• Martin, R.H. and Davidson, B.D., “Mode II Fracture Toughness Evaluation Using a Four Point Bend End Notched Flexure Test, Proceedings of 4^th International Conference on Deformation and Fracture of Composites, Manchester, 1997, pp 243–252.
• Paraschi, M., “A Fracture Mechanics Approach to the Failure of Adhesive Joints,” PhD Thesis, Department of Mechanical Engineering, Imperial College, London, 2002.
• Blackman, B.R.K., Kinloch, A.J. and Paraschi, M., “The Determination of the Mode II Adhesive Fracture Resistance, G_IIC, of Structural Adhesive Joints: An Effective Crack Length Approach,” Engineering Fracture Mechanics, Volume 72, 2005, pp 877–897.

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