Influence of Structural Parameters-the Shape of Graphite and Matrix on Change of Ultrasonic Wave Propagation Rate and Value of Attenuation in Graphitic Cast Irons

Despite the tendency of the current industry, especially the automotive industry, it is to use modern, light and super-strong materials based on Al or HSLA steels, the application of classic materials such as cast iron still makes sense, especially concerning price and excellent castability. The article presents one of the possible ways of using the ultrasonic non-destructive method in quality control and simplification of the identification of the type of cast iron concerning the change of parameters of ultrasound propagation in materials. The main criteria for assessing the quality and determining the type of graphite cast iron were considered to be the rate of propagation of ultrasound - c(L) and the value of attenuation - alpha, which vary depending on the shape of the graphite and matrix. Graphitic cast irons with different graphite shapes (lamellar, vermicular, and globular shapes) and a matrix with different ferrite/perlite ratios were used as experimental material. Along with the ultrasonic tests, a metallographic analysis was also performed to quantify the microstructure of cast irons.

Automated summary

Despite the trend in the automotive industry towards using modern materials based on Al or HSLA steels, cast iron still holds value due to its price and excellent castability. This article explores the use of ultrasonic non-destructive testing to simplify the identification of cast iron types based on ultrasound propagation parameters. The main criteria for assessing quality and determining the type of graphite cast iron are the rate of ultrasound propagation (c(L)) and the attenuation value (alpha), which vary based on the graphite and matrix shape. The study involved different graphite shapes and matrix ratios, and metallographic analysis was also performed.