The influence of non-metallic inclusions in steel on the quality and performance of steel castings is not only related to the number of inclusions, but also closely related to the type, shape, size, deformation behavior and distribution of the inclusions. Large-scale low-carbon steel castings have low carbon content in the steel. Its smelting and solidification characteristics determine that the castings are prone to form defects such as microscopic inclusions and cracks. Even if there are a small amount of non-metallic inclusions in the rudder arm, it is enough to affect its mechanical mechanics performance.

• (1) The calculation of the equivalent stress field distribution of the inclusion and its surrounding matrix under variable loads under uniaxial tension, and the establishment of the micromechanical behavior model of the inclusions. , Calculated the stress distribution under uniaxial tension. Under the same physical parameters, the stress occurs at the interface between the inclusion and the matrix perpendicular to the uniaxial stretching direction, and should occur in the inclusion. The stress distribution in the circular inclusions is relatively uniform and the stress is relatively small; while the stress distribution in the pentagonal inclusions is uneven and the stress is not uniform. The influence of the orientation and spacing of inclusions on the stress distribution is studied. The orientation and spacing of the circular inclusions have little effect on the stress distribution; when the orientation of the inclusions is parallel to the tensile force, the stress will occur in the interior of the square inclusions. The stress increases rapidly as the inclusions approach. When the distance between the two inclusions increases to twice the diameter of the ball, the influence of the spacing on the stress decreases.
• (2) Developed a special rare earth composite refining modifier to improve the shape and distribution of inclusions
  According to the above analysis results, in order to make the inclusions in the steel small, spherical and dispersed, reduce the stress concentration on the matrix and weaken the harm of the inclusions, a special rare earth composite refining modifier has been developed to improve the shape of the inclusions. And distribution, improve the mechanical properties of castings. Adopting the technical idea of increasing the core of crystal nucleus and preventing the preferential growth of the sharp corners of inclusions, and by studying the relationship between the modifier components and the shape of the inclusions, a special modifier was developed; v and Ti are used as the core of the foreign crystal nucleus to increase the crystal nucleus The quantity, refines the crystal grain; the rare earth element as the surface active element preferentially grows at the front of the crystallization, so that the inclusions are passivated or rounded.

Link to this article：The influence of non-metallic inclusions in steel on the quality and performance of steel castings

Reprint Statement: If there are no special instructions, all articles on this site are original. Please indicate the source for reprinting:https://www.cncmachiningptj.com/，thanks！

3, 4 and 5-axis precision CNC machining services for aluminum machining, beryllium, carbon steel, magnesium, titanium machining, Inconel, platinum, superalloy, acetal, polycarbonate, fiberglass, graphite and wood. Capable of machining parts up to 98 in. turning dia. and +/-0.001 in. straightness tolerance. Processes include milling, turning, drilling, boring, threading, tapping, forming, knurling, counterboring, countersinking, reaming and laser cutting. Secondary services such as assembly, centerless grinding, heat treating, plating and welding. Prototype and low to high volume production offered with maximum 50,000 units. Suitable for fluid power, pneumatics, hydraulics and valve applications. Serves the aerospace, aircraft, military, medical and defense industries.PTJ will strategize with you to provide the most cost-effective services to help you reach your target,Welcome to Contact us ( sales@pintejin.com ) directly for your new project.