Question

Question 3 1 pts Explain the following sentence: The ram speed is high when steel is extruded, whereas it is lower when alunimum is extruded.

Answer 1

Answer:

The statement as given above in the question can be understood as per the explaination given below

The main factors which affect the quality in the extrusion process are design of die, extrusion ratio which depens upon area, lubrication and ram speed during extrusion process.

Ram speed also affects the quality of the material produced so that the selection of ram speed to be carried out wisely for different materials . The profile,geometry and materials used in the complex shape manufacturing affects the flow of metal and the pressure required for the metal flow.

Steel material required higher ram speed for the extrusion and aluminium materials required less ram speed for the extrusion process. Applied strain rate is directly related to the ram speed of the extriusion press. Product surface which is produced by the base material extrution, is an inportant indicator of the quality of the extruded product from aluminium and steel.Speed of the extrusion ram affects the life and product quality which is to be used properly.

Steel materials density is higher and generally they are extruded with the hot extrusion process. Sppeed of the ram in the process is kept higher to eliminate the heat transfer problem from the billet to the tools.Extrusion pressure is increases in case of higher ram speeds.

When aluminium is extruded with lower and higher speed of the ram, there are significant changes are shown in the thermal condition of the struded material. Metal flow is also different at lower and higher ram speeds because of the concerrent change in the temperature field of the material of the billet. Aluminium is ductile material and generally colled extruded so to maintaine the intricate shapes of the product, aluminium are extruded at the lower ram speeds as higher speed can cause surface textures problem.Low ram speeds leads to the cooling of the billet and due to that the flow stress is increased

Apart from the above given explaination, the ram spped effect can be seen as given below points clearly as

• In case of higher temperature of billets, the low speed of the ram has the higer effect on the cooling of the billet.
• So thats why the higer speeds of ram is required for the high strength alloys like steels which requires higer extrusion temperature
• Apart from this, at higher ram speed of extrusion, temperature rise during extrusion is higer
• Temperature and ram speed for any material generally selected by the trial and error methods