A B S T R A C TThe 6000 series aluminium alloys (Al-Mg-Si systems) are commonly used as mediumstrength structural materials; in particular, the 6061 (Al-1Mg-0.6Si) alloy is widely utilized as a general-purpose structural material due to its excellent formability and corrosionresisting capabilities. The objective of this study was to obtain a correlation between the small punch (SP) test estimated equivalent fracture strain (ε qf ) and fracture toughness (J 1C ) property for 6061 aluminium, and determine its viability as a non-destructive fracture toughness test technique for remaining life assessment of in-service components. Samples of 6061-T6 aluminium were cut from bulk plate, in both the longitudinal and transverse directions, for the as-received condition as well as subjected to three different over-ageing heat-treatment schedules. A strong linear correlation between valid J 1C and SP estimated biaxial fracture strain ε qf is presented for aluminium 6061 at room temperature.Keywords aluminium alloy 6061; equivalent fracture strain; in-service component; J integral fracture toughness; remaining life assessment; small punch test. N O M E N C L A T U R EF UPTHRUST = upthrust due to sample in water J 1C = valid J integral fracture toughness J 0 = material/environment dependent empirical constant k = material/environment dependent empirical constant m DRY = dry weight of aluminium m WET = wet weight of aluminium n = empirical parameter in small punch correlation R 2 = correlation coefficient for least squares curve fit t 0 = original thickness of small punch disk t = thickness of small punch disk at fracture T SP = transition temperature in small punch tests w CT = critical strain energy density of compact tension sample w SP = critical strain energy density of small punch sample x = material dependent characteristic averaging distance β = empirical parameter in small punch correlation δ = small punch deflection at fracture ε qf = equivalent biaxial strain at fracture ρ Al = density of aluminium ρ H2O = density of water

Thermomechanical training was carried out on a newly developed Fe-20Mn-6Si-7Cr-1Cu shape memory alloy. It was observed that the effectiveness of thermomechanical training largely depends on the recovery annealing temperature and the pre-strain during training. Based on the analysis of the changes in critical stress for martensite formation, the critical stress for slip deformation, the phase transformation temperatures and microstructural development during training, it was concluded that the mechanism of thermomechanical training is based on the following two factors : (1) lowering of the critical stress for martensite formation, making stress induced γ→ε transformation easier ; and (2) decreasing the Af temperature and refining the ε martensite structure, thus reducing the energy barrier for the ε→γ reverse transformation. The optimum thermomechanical training conditions have been determined for the alloy studied

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Two Ni-Cu alloys (Monel K500 and FM 60) having various Mn, Fe, Al, Ti and C contents were deposited on a Monel K500 plate at three different speeds using wire arc additive manufacturing technique. Microstructure characterisation, in particular a detailed study of precipitates, was carried out using optical and scanning electron microscopy. Mechanical properties were assessed using hardness, tensile and wear testing. For similar deposition conditions, Monel K500 has exhibited smaller secondary dendrite arm spacing and higher number density of Ti-rich particles, although the Ti concentration in FM 60 was higher. Finer microstructure and Ti precipitation led to superior hardness, tensile and wear resistance of Monel K500 compared to FM 60. The variation in microstructure-properties relationship with alloy composition is discussed.