Study on Improvement of Casting Conditions for Some Aluminum Bronze Alloys

Abstract

Two types of aluminium bronze alloys have been studied to determine theproper methods of melting and casting in two different conditions; with treatingmaterials as (Albral 2, Logas 50 and deoxidizing tube E3) and without anddetermine the effects of these conditions on mechanical properties of alloys.These alloys are :-a) Aluminium bronze alloys (AB1).b) Nickel-aluminium bronze alloys (AB2).These alloys were produced using different melting processes and cast method.The first one was made by preparing the charge materials to be melted andthen, to the cast process without using any types of additions and treatmentmaterials. The second one was made with casting conditional control, usingproper techniques of casting and using protective layers to minimize theoxidation and other casting defects. The molten metals from both processeswere poured into two types of moulds; sand and metal moulds, both types werein dimensions (Ø100×250) mm.The final products of each type of alloys in each type of conditions were used toperform many types of inspections; chemical analysis, visual test, structureexaminations, hardness test and tensile test.The results of all processes and inspections show that the properties of alloyswhich were treated and cast in metal moulds were better than that cast in sandmoulds. These alloy castings are free from shrinkage cavities, inclusions andporosities due to using suitable sequence in alloy contents melting, no overheat,reducing the melting time, selecting non-turbulence casting method and suitableselection of pouring temperatures. The mechanical properties (hardness andultimate tensile strength) for treated nickel-aluminium bronze alloys (T-AB2)were better than that for other alloys.