Frequently Asked Questions about Engineering Materials

What is electrical steel?
A: Electrical steel, also known as silicon steel, transformer steel or e-steel, is an iron-silicon alloy that differs from ordinary steel, i.e., an iron-carbon alloy. Common cold rolled electrical steel usually contains no more than 3.2% silicon, while hot rolled electrical steel may have a higher silicon content, usually no more than 4.5%. Electrical steel is usually produced in sheet and coil form and is often processed in stacked form. It is important to note that this steel usually comes with a barrier layer.

What is the difference between "High Temperature Superalloys (HTSA)" and "Heat Resistant Superalloys (HRSA)"?
A: The definitions of "High Temperature Superalloy" and "Heat Resistant Superalloy" refer to alloys that are specifically designed for use in high temperature environments. Essentially, both terms refer to alloys that have high-temperature properties and are able to perform at high temperatures without significant degradation. As a result, the terms are often used interchangeably in many cases, but strictly speaking there are some differences between the two.

"High-temperature superalloys" (HTSA) generally refer to alloys that are capable of retaining their strength and mechanical properties at very high temperatures, typically above 1000°C (1832°F). These alloys are used in applications such as gas turbines, jet engines and rocket propulsion systems.

E-steel
A: Electrical steel.

Spring pass, spring cut (Repeat pass, repeat cut)
A: Additional passes at the same setting, primarily used in turning, drilling and threading operations. The aim is to thoroughly clean the machined surface and ensure the required precision. Due to the flexibility of the technical systems and the thermal deformations generated during machining, which may affect the final dimensions achieved by means of conventional tool walking, the need for repeated tool walking is increased in practical machining. In turning, repetitive tool travel is usually achieved by reversing the feed of the tool.