Effects of Ultrasonic Treatment during the Solidification Process on the Structure Formation of Low Carbon Steel
This paper studied effects of ultrasonic treatment during the solidification process on structure formation of low carbon steel. Results showed that with ultrasonic treatment grains were refined and the steel ingot avoided the cast widmanstatten structure. When ultrasonic treatment was employed, pearlite was broken and the average length of pearlite was decreased from 550 mm to 140 mm. The corresponding aspect ratio was reduced from 12 to 1. At high magnification the treated pearlite was cloud-like, rather than plate-like, as normal. Ultrasonic treatment also can remove the gas from low carbon steel. These phenomena of low carbon steel generated by ultrasonic treatment were explained. [doi:10.2320/matertrans.M2011091]
Effect of Ultrasonic Inoculation Treatment on Distribution of Sulphur in Fe-S Alloy
Influence of ultrasonic inoculation treatment on distribution of sulphur in Fe-S alloy was mainly studied. Results showed that Ultrasonic treatment could reduce the segregation degree of sulfur in Fe-S alloy and make the distribution more uniform. When the ultrasonic treatment time was 60s, sulfur segregation was in the lowest of 0.3799, and homogeneity was in the maximum of 0.5470.While treated with ultrasonic power of 150W, sulfur segregation was 0.5068, and sulfur segregation was improved, but homogeneity of sulfur decreased to 0.3411, overall homogeneity distribution of sulfur decreased.
Effects of power ultrasonic treatment on microstructure and mechanical properties of T10 steel
The microstructure and mechanical properties of T10 steel treated with power ultrasonic during solidification are investigated. A self-developed experimental setup is built for the propagation of ultrasonic vibration into the melt along the horizontal direction. Experimental results indicate that the power ultrasonic applied in the melt can not only refine the microstructure remarkably but also enhance both tensile strength and ductility values of T10 steel. Furthermore, the finer grains can be obtained due to the higher incident ultrasonic power. SEM fractographs show that the sample with 600 W ultrasonic treatment exhibits a ductile fracture surface covered with deformation dimples, while the sample without ultrasonic treatment shows a brittle fracture surface. The effects of power ultrasonic on the melt are discussed.