PROCESS FOR PRODUCING AN ALUMINUM ALLOY SHEET

摘要

A CONTINUOUSLY CAST AND ROLLED SHEET OF AN ALUMINUM ALLOY HAVING MG IN A CONTENT OF 3 TO 6% BY WEIGHT IS ANNEALED, FOLLOWED BY STRAIN CORRECTION, HEAT AND HOLD TREATMENT AT GIVEN TEMPERATURE BETWEEN 240°C AND 340°C FOR ONE HOUR OR MORE, AND SLOWLY COOLING TREATMENT, TO THEREBY PROVIDE AN ALUMINUM ALLOY SHEET HAVING ENHANCED RESISTANCE TO STRESS CORROSION CRACKING AND IMPROVED SHAPE FIXABILITY.THE SLOWLY COOLING TREATMENT IS CARRIED OUT AT A COOLING RATE CHOSEN FROM A PRESET COOLING ZONE CORRESPONDING TO A PRESET TEMPERATURE ZONE S DEFINED IN OBLIQUELY LINED SURROUNDED FROM IN THE ACCOMPANYING DRAWING.(FIGURE 1)