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Fibre metal laminates (FML) are the modern hybrid materials with potential wide range of applications in aerospace technology due to their excellent mechanical properties (particularly fatigue strength, resistance to impacts) and also excellent corrosion resistance. The study describes the resistance to low velocity impacts in Ti/CFRP laminates. Tested laminates were produced in autoclave process. The laminates were characterized in terms of their response to impacts in specified energy range (5J, 10J, 20J). The tests were performed in accordance with ASTM D7137 standard. The laminates were subjected to impacts by means of hemispherical impactor with diameter of 12,7 mm. The following values have been determined: impact force vs. time, maximum force and the force at which the material destruction process commences (Pi). It has been found that fibre titanium laminates are characterized by high resistance to impacts. This feature is associated with elasto-plastic properties of metal and high rigidity of epoxy - fibre composite. It has been observed that Ti/CFRP laminates are characterized by more instable force during impact in stage of stabilization of impactor-laminate system and stage of force growth that glass fibre laminates. It has been observed more stable force decrease in stage of stress relaxation and withdrawal of the impactor. In energy range under test, the laminates based on titanium with glass and carbon fibres reinforcement demonstrate similar and high resistance to low-velocity impact, measured by means of failure initiation force and impact maximum force. [ABSTRACT FROM AUTHOR]

Results of a study of silica and silica–titania sol–gel coatings for the creation of intermediate interfaces between commercially pure Ti or titanium alloy Ti6Al4VELI and dental porcelain are presented. Coatings of SiO2 on Ti6Al4V alloy and SiO2–TiO2 on Ti were deposited using sol–gel method. Surface microstructures and wear behaviour of the coatings were studied by using scanning electron microscopy with electron diffraction spectroscopy and pin-on-disc method. It is found that (1) Ti6Al4V/SiO2 and Ti/SiO2–TiO2 coatings obtained by the sol–gel method are compact, chemically homogeneous and relatively rough, and (2) the smaller wear of SiO2 coatings than that of SiO2–TiO2 coatings is associated with differences in their microstructure and roughness. [Copyright &y& Elsevier]

• The objective were Hybrid Titanium Carbon Laminates as a second generation of FML. • The fibre orientation in HTCL has a significant influence on damage propagation. • Dominant failure occurs at the metal/composite and composite/composite interfaces. • HTCL can be an appropriate solution for materials under dynamic loads. Impact resistance is one of the more critical and important features of composite materials used in the aerospace industry. The objective of work was to evaluate the hybrid titanium carbon laminate resistance to dynamic loads. The paper utilizes numerous criteria for evaluation of impact behaviour of materials, including force change, energy absorption characteristics and failure identification. To thoroughly analyze the damage mechanism, a detailed fractography of laminate destruction was performed. Moreover, an empirical model for determining the universal impact behaviour coefficient of fibre metal laminate (FML) was proposed. The first significant force fluctuations prove to reach the laminate's impact resistance limit as caused by the initiation of cracking of respective layers and the consequent reduction of laminate rigidity. A growing proportion of absorbed energy in the case of growing impact energies, from some 50% in case of 2.5 J of energy, up to circa 80% in case of 30 J of energy was recorded. Reduction of interlayers with crossing fibers fosters the creation of cracks in the lower layer of titanium due to the limited capability of partial absorption of energy through delamination. [ABSTRACT FROM AUTHOR]