Application of Low Melting Point Alloy Method in Fixing of Stamping Die Parts

Low melting point alloys, also known as fusible alloys, refer to binary, ternary or multi-element alloys with bismuth, lead, tin, antimony, molybdenum, etc. as the main components. According to different application requirements, the mass fraction of each metal element in the alloy is also different. Low melting point alloys have the characteristic of volume expansion when they are condensed. Use this feature to fix the punches, dies, guide posts, guide sleeves, and plastic holes of the discharge plate in the stamping die assembly. 1) The advantages of the low melting alloy method. (1) Low melting point, easy melting (the alloy melting point is below 200℃), simple process, convenient operation, and can reduce the processing accuracy of the matching parts and reduce the processing man-hours. Therefore, it is suitable for the fixing of multiple punches and complex small punches of stamping dies. (2) The bismuth-based low melting point alloy has cold expansion characteristics when the molten metal is condensed. (3) It has a certain strength (tensile strength of 38~91MPa), and is suitable for fixing punches of steel plates with a stamping thickness of ≤ 2mm. 2~3 times. When there are many recycling times, the alloy composition ratio should be measured to make up for the metal elements lost due to repeated recycling and melting. 2) Using low melting point alloy to fix the structure of the punch of the stamping die. An example of pouring low melting point alloy is shown in the figure. 3) The disadvantages of the low melting point alloy method. (1) Relevant mold parts should be preheated before pouring. (2) The stamping die is prone to thermal deformation. (3) The precious metal bismuth is consumed. Due to the need for sufficient clearance between the mating surfaces to allow the alloy to be poured in during bonding, the positioning of the mold is difficult, and the ability to withstand large loads and strong impacts during use is not enough, and the current wide use of wire cutting and EDM technology processing Stamping dies, so the low melting point alloy method has been gradually eliminated. Previous post: Cross-section characteristics of metal stamping parts, don’t be confused after reading