Influence of modification by superdispersed powder of aluminum oxide on lead-tin bronze structure

Lead-containing tin bronzes are a good antifriction material. The area of their application is limited because of low strength properties. It is possible to enhance the strength properties by changing their structure using modification by nanopowders. This article presents data on the influence of admixtures of the aluminum oxide nanopowder on the structure of the cast bronze (with lead and tin). For the castings, containing different amounts of the prepared modifier based on aluminum oxide, metallographic studies and structural studies were undertaken. Based on the results of the work, the concentrations of the aluminum oxide nanopowder in the modifier, strongly influencing the structure of the castings, have been chosen. It has been shown that even small admixtures of the modifier (0.07-0.25%) based on aluminum oxide allow refining the casting grain, reducing the average size of lead inclusions and forming a dispersed network of eutectoid inclusions.