1. Hardness test The sampling position of the hardness sample of the gray cast iron cylinder block is shown in Figure 1. The hardness test of the cylinder position needs to test the hardness for 3-4 times at equal intervals to test whether the hardness distribution of the cylinder...
1. Metallographic observation The metallographic sample is taken from the gray cast iron cylinder body, cut and sampled with a cutting machine, and the sampling position is shown in the figure. The removed samples are inlaid with epoxy resin, ground on 120, 280, 400 and 500 sandpaper respectively, and...
Figure 1 shows the model and production flow chart of a high-strength gray cast iron engine cylinder block. The main processes include raw material ratio, baking process, molding, core making process, pouring process and post-treatment process: (1) Ingredients; The ingredients are divided into raw materials and auxiliary materials. According...
Gray cast iron is mainly composed of matrix structure and graphite, and others include eutectic, carbide and cementite eutectic. Its microstructure determines its performance. When observing its metallographic structure, it is mainly analyzed and studied from the aspects of flake graphite, metal matrix and eutectic at grain boundary. The...
To do a good job of Si-Mn alloyed nodular cast iron grinding ball, first of all, spheroidize the nodular cast iron grinding ball well. The size and quantity of graphite balls are uniform. The spheroidization grade should be I-II, as shown in Figure 1 and Figure 2. The whole...
Cast iron generally refers to multi-component iron carbon alloy with C content of 2.0% (wt%, the same below) W. Generally, the C content of industrial cast iron is 2.5-3.5%. C exists in gray cast iron in the form of W graphite and a small amount of W PA C....
The heat treatment process of Si Mn alloyed ductile iron is similar to that of other ductile iron, which can be generally divided into three stages: heating, quenching, tempering or isothermal. The heating process curve is shown in Figure 1. The heating at the low temperature stage shall be...
The above improvement scheme is used to verify the pouring production. Figure 1 is the foam pattern cluster and the deformation prevention treatment. The production results of the improved scheme are shown in Figure 2. No significant shrinkage defects are found when the shaft sleeve is cut open, and...
The quenching medium used for nodular cast iron grinding ball should have the following two characteristics: 1) The quenching medium has a fast cooling rate at the high temperature stage of the grinding ball; 2) The quenching medium has a slow cooling rate at the low temperature stage of...
The mold filling and solidification of the improved process are simulated, and the following results are obtained: 1) Results of lost foam casting filling process From the filling time of lost foam casting, the maximum filling time of double-layer stepped type is 16.64s. Due to the use of double-layer...