1. Transverse cracks. There are generally two forms of transverse cracks: surface transverse cracks and transverse cracks. Surface transverse cracks are caused by low quality of raw materials or excessive hammer feed during drawing; The transverse cracks are mainly caused by too fast heating speed or too small hammer feed when drawing.

2. Longitudinal cracks. Tongye Town can be divided into two types: longitudinal surface crack and longitudinal surface crack. The longitudinal surface crack is mainly caused by poor quality of raw materials or excessive reduction during chamfering. The causes of longitudinal crack are similar to ingot drawing, insufficient secondary shrinkage cutting head or fast heating speed, and large temperature difference between inside and outside. It may also be caused by too large deformation of low plastic X material, too large hammer feed and repeated overturning of the same part.

3. surface. The forging temperature is too high.

4. Coarse crystal part. High heating temperature or uneven deformation, and too small deformation (forging ratio).

5. Surface folding. Because the fillet of the flat anvil is too small or the hammer feed is less than the reduction.

6. Migration. Because the heating temperature is not uniform or the amount under the operating pressure is not uniform.

7, mechanics is in line with the requirements. Defects such as unqualified degree index caused by quality requirements of steelmaking or improper heat treatment, unqualified transverse mechanics caused by excessive melting impurities or insufficient forging ratio.

Utilization of waste heat from hot forging of aluminum alloy forgings

Forging industry is a household with high energy consumption, and the energy consumption of forging heat treatment accounts for about 30%~35% of the total energy consumption of forging production (its quantity is related to the utilization of forging waste heat and the application of non-quenched and tempered steel). The energy consumption per ton of die forging in China is about 0.8t~1t standard coal. Compared with foreign industrialized countries, the energy problem is an important issue for a country's sustainable development, and even a major global issue for human survival.

Heat treatment is a process with high energy consumption, so it also has great energy-saving potential. There are also three kinds of wastes (waste gas, waste water and waste residue) which pollute the environment. Therefore, the improvement of heat treatment process, process materials and heat treatment equipment for forgings is an important way for forging enterprises to save energy and reduce emissions.

Making full use of the forging waste heat of forgings for heat treatment not only has obvious advantages in saving energy, reducing consumption and improving efficiency, but also reduces the discharge of three wastes, which is energy-saving and environmentally friendly. Carbon structural steel and low-alloy structural steel are widely used in mechanical parts. The most commonly used heat treatment processes for forgings are normalizing, isothermal normalizing, annealing and quality adjustment.

1. Energy consumption of quenching and tempering: continuous resistance furnace is adopted, the quenching temperature is 840℃~860℃, and the actual power consumption per kg forging is about 0.6kwh. The continuous resistance tempering furnace is adopted, the tempering temperature is 550℃~650℃, and the actual power consumption per kg forging is about 0.4k K.

2. Normalization energy consumption: continuous resistance furnace is adopted, the normalizing temperature is 930℃~960℃, and the actual power consumption per kg forging is 0.5kwh.

3. Isothermal normalizing energy consumption: continuous resistance isothermal normalizing furnace is adopted, the heating temperature is 920℃~940℃, the cooling speed is fast, and the isothermal temperature is 600℃~650℃, and the actual energy consumption per forging is about 0.8kwh.

The above data counts the actual average value of continuous resistance furnace throughout the year. For example, the unit power consumption of continuous casting chain resistance quenching furnace for 24 hours production is about 0.5kwh/kg. However, the actual power consumption per kg forging is 0.6kwh due to repeated temperature rise due to failure and shutdown in the production process throughout the year.

The above data are for reference only, because the heat treatment energy consumption of forgings is determined by furnace type, loading mode, steel type and production mode, and the energy consumption of periodic heating furnace is greater than that of continuous heating furnace. For example, the energy consumption loss of continuous mesh belt resistance furnace or continuous cast chain resistance furnace is small, while the energy consumption loss of vehicle resistance furnace is large.

Link-B2B is a professional supplier listing service platform which will provide high quality and trustworthy supplier list to international buyers. If you are looking for aluminum alloy forgings suppliers, feel free to visit Link-B2B.com and send a request.