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Marine Materials Representatives of aluminum producers, boat builders and classification societies actively participated in the ASTM spec- ification development process, which in addition to electronic distribution and balloting, included two ASTM task group meetings held in conjunction with ASTM committee weeks in November 2002 and May 2003. Key elements of this new specification (ASTM B 928 "High Magnesium Aluminum-Alloy Sheet & Plate for Marine Service") are the requirements that the referenced materials be capable of meeting the corrosion requirements of both ASTM G 66 (Test Method for Visual Assessment of Exfoliation Corrosion Susceptibility of 5xxx Series Aluminum Alloys (Asset Test)) and ASTM G 67 (Test Method for Determining the Susceptibility to Intergranular Corrosion of 5xxx Series Aluminum Alloys by Mass Loss After Exposure to Nitric Acid (NAMLT Test)). Another significant aspect of the specification is that the requirement applies to both the HI 16 and H321 tem- per designations for high magnesium aluminum alloys. Concurrent with the ASTM activities, the Aluminum Association task group continued to meet to supply input on the draft specification as well as to address additional alloy-temper product registra- tions that will be included in future revi- sions to ASTM B 928. which are already underway. In addition The Aluminum Association's Technical Committee on Product Standards, which is the North American registrar of alloy-temper product registrations, will restrict the assignment of the HI 16 and H321 tem- per designations to 5xxx alloys with a nominal magnesium content equal to or greater than 3% and which have the capability of meeting the corrosion requirements of both ASTM G66 and ASTM G67. In the near future, the alloys and tempers covered by ASTM B 928 will be removed from ASTM B 209 making ASTM B 928 the sole ASTM material specification for Marine Sheet and Plate. At this time, the introduction of this new material specification is for the information of aluminum end-users in NAVAL ARCHITECTS I MARINE ENGINEERS Circle 286 on Reader Service Card Circle 317 on Reader Service Card 60 Maritime Reporter & Engineering News • Large super-bright Digital Heading Display. • Analog Turning Indicator - allows instant estimation of the ship's turning rate. • Will work from most types of gyro compasses. • Repeaters can be "daisy chained" and synch- ronized to first repeater (Master Repeater). • Digital Data output. NMEA and various other protocols are available for integration with survey and navigation computers. SCAN DIGITAL HEADING REPEATERS P.O. Box 155, 1001 South Andrews Avenue, Suite 120, N-1411 Kolbotn, Norway, Fort Lauderdale, Florida 33316, USA Phone: +47 6681.2740 Phone: +1.954.523.8878 Fax: +47 6680.8095 Fax: +1.954.523.7157 E-mail: sales@scansys.no E-mail: sales:g'scansys.no Scandinavian micro systems Digital Gyro Repeater Now also compatible with AIS