Company name: wuxi tianfeng metal products co. LTD
Address: no. 39, zhenze road, huazhuang street, economic development zone, wuxi city, jiangsu province (old factory area)
Address: no.210-2, chengnan road, wangzhuang industrial supporting area (new), new district, wuxi city, jiangsu province
Contact person: +86-1377 1199 895
Tianfeng metal on the shaft forgings of low - strength sulfur seal test
Sulfur print test is a macroscopic test method to show the sulfur distribution in iron and steel. With the crystallization of molten steel and the process of gas precipitation, a variety of different substances due to the results of selective crystallization and segregation, generally, the larger the ingot, the more severe segregation, which brings different degrees of influence on the performance and quality of steel.
The basic principle of the sulfur printing test is, according to the sulfur in the form of sulfide in steel, with dilute sulfuric acid and its effect to produce hydrogen sulfide gas, then the hydrogen sulfide gas produced and silver bromide on the photographic paper, silver sulfide precipitation, the sediment is dark brown traces and appeared on the photographic paper. When the sulfide content in the steel is high, the dark brown silver sulfide traces on the photographic paper are also large, and the color is dark. Conversely, trace is lesser, color is lighter. Therefore, the size and content of sulfide in steel can be reflected according to the size, color and distribution of brown marks on the forging paper. Thus, the segregation degree of sulfur in steel can be determined qualitatively according to inspection results and inspection standards, and the quality of forgings can be preliminarily evaluated.
The standard experimental method is specified in the standard, and the standard rating is established according to the characteristics, distribution and density of sulfur print segregation. This standard includes:
1. Classification of sulfur print results. The results were divided into spot segregation and ingot segregation, and the grading pictures were attached. A. point segregation. B. ingot segregation.
2. Assessment principles. The point segregation level is determined according to the degree of expansion of the segregation point from the center to the outer circle, the size of the point, the density and the depth of the color. The point segregation is divided into the point segregation rating picture without the central hole and the point segregation rating picture after the central hole.
3. Assessment methods. The sulfur print rating is determined by comparing the sulfur print image with the standard sulfur print image. When there is a difference between the sulfur print picture and the standard rating picture of the segregation point, according to the size of the point, the width of the band, distribution area, density and color differences, etc.