MATERIALS • PROCESSES • FINISHES
Users of the new steel can forge their material to near net shape
FORGING AHEAD T
Patrik Ölund explains how the latest addition to a family of steel products is creating new opportunities for near net shape forming operations
raditionally, steels were classified into four general categories: tool steel, stainless steel, engineering steel and maraging steels. In 2017, the
launch of Ovako’s Hybrid Steel created a new family of grades with an innovative alloying philosophy. Te result is that the key properties of each category are available in one high-performance steel (Fig.1.). Te family has now grown to include
Hybrid Steel 50, a grade that offers exciting possibilities for component manufacturers to dispense with the need for quenched and tempered steel. By using the new grade, they can forge their component to near net shape, machine it in a soft condition and then apply a simple ageing treatment to achieve the final hardness required. Two well-established precipitate phases
are combined to strengthen Hybrid Steel: alloy carbide and inter-metallic. It also uses a creative alloying philosophy that minimises segregation. An important feature is that the significant levels of aluminium
36
www.engineerlive.com
enable a strong combination of attractive properties. Tis is because aluminium reacts with nickel to form very small inter-metallic precipitates, but nearer the surface it also helps to form a protective oxide barrier. Te steel is ideal to meet the demands of high-stress, elevated-temperature applications where mechanical and fatigue strength are critical. It also offers good
resistance against corrosion and oxidation, as well as good weldability. Furthermore, unlike some niche steel grades, Hybrid Steel is produced without the need for expensive small-batch processes.
A NEW GRADE FOR LOWER HARDNESS APPLICATIONS Hybrid Steel 60 and 55 were the first two commercial grades in the family. Te naming results from the hardness they are designed to: 60 and 55 HRC, respectively. Hybrid Steel 60 is a new grade of bearing steel for applications where added strength is needed. Hybrid Steel 55 suits an array of engineering steel needs. Following the launch of Hybrid Steel,
Fig.1. Properties of Hybrid Steel
Ovako began to receive enquiries from manufacturers of critical high-strength components, especially in the automotive industry. Teir aim was to find an alternative to the quenched and tempered steels in current use. Tey do perform well, especially in terms of strength, toughness and fatigue life. However, there are some downsides,
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52
