Wood pallets are increasingly stored in warehouses with drive-in or drive-through racks. A pallet needs adequate stiffness and strength to function safely under conditions where it spans the rack support rails. When the stringers run parallel to the supports, the fasteners reinforce the deckboard load-carrying ability. This report experimentally determines the effect of fasteners on pallet performance. The effect is characterized in terms of the ratio of the joint rotation modulus to a normalized deckboard bending stiffness. This approach enables the joints to be compared with pinned and rigid joints in a pallet stiffness and strength theory.

The Top-on ultrasonic method proposed earlier was applied to the rising load KIscc testing and the validity was confirmed by comparing the determined KIscc values with those measured according to the conventional longtime KIscc testing in the same environments. In addition, the influences of loading rate, fatigue precracking stress intensity level, and fracture morphology of fatigue precracked zone on KIscc were discussed.

Alloys of iron-aluminum-manganese containing over 8% aluminum can be made completely austenitic and have good ductility and toughness. Oxidation resistance is good at temperatures up to 982°C (1800°F), but embrittlement occurs following heating in the range 538 to 760°C (1000 to 1400°F). Resistance to corrosion by aqueous environments is poor.

A brief account is given of the principles of dual-energy computerized tomography (DECT) and of the potential which DECT has demonstrated for the automated detection of commercial and military explosives concealed in suitcases or packages. A description of a breadboard system configured for this purpose is provided and recent advances in the state of the art in CT are discussed in the light of their potential significance for explosives detection.

Fracture toughness δi of AISI 4340 steel in the hardened and tempered condition has been determined by the multiple-specimen CTOD (crack tip opening displacement) resistance curve method. This fracture toughness δi value has been compared with the JIc fracture toughness also obtained by the multiple-specimen JR curve technique. The investigation also examines the effect of specimen size, thickness, and width on δi and δR curve behavior. The effect of these parameters on the constraint factor m in the J-δ relationship has also been examined. Compact tension specimens with TL orientation were used. All specimens satisfied ASTM E 813 standard size requirements. This investigation demonstrates that Jδi values obtained by the CTOD resistance curve method are similar to JIc values obtained from the J-integral resistance curve method. The specimen thickness has no significant influence on δi or δR curve behavior. On the other hand, specimen width has a distinct influence on constraint factor m and δR curve behavior.