Thermal Expansion of Stainless Steels: Part One

The coefficient of thermal expansion effectively measures the rate of the material expansion as a function of temperature.
This is a critical measure of the material where the application infers heating and remaining at a fixed dimension for any period of time. Continue reading

Titanium-Nickel Shape Memory Alloys

Shape memory alloys are categorized by two very unique properties; pseudo-elasticity (PE), and the shape memory effect (SME).
Since SMA’s are hugely versatile and functional materials they have a range of important applications to fulfill including bone transplant replacements, sensors, antennas for mobile phones and much more. Continue reading

Steel Bending

There are five typical methods of bending currently used in industry today: rolling, incremental bending, hot bending, rotary-draw bending, and induction bending.
Although ISF is generally very slow, it is of interest because no or only a simple and cheap tool is required, making the process ideal for small-series production. Continue reading

Vacuum Brazing: Part Two

A critical step in any brazing process is the successful removal of oxide films before the process begins and the vacuum brazing process is no different.
In order to prepare the mating surfaces for brazing the ‘clean-up’ process needs to be initiated and this typically happens most effectively between 600 and 850°C. Continue reading

Low Temperature Carburizing of Austenitic Stainless Steel: Part One

Although austenitic stainless steels are among the most commonly applied corrosion resistant steels challenges exist related to their relatively poor surface hardness and wear resistance.
Low temperature carburizing presents an effective solution to these challenges by increasing surface hardness through a carbon rich diffusion zone which does not compromise the corrosion resistance of the material. Continue reading

Vacuum Brazing: Part One

Vacuum brazing is categorized as a technique by its protected sealed environment under vacuum and extremely high temperatures greater than 800°C.
The main advantages of using vacuum brazing include achieving high integrity hermetic joints with minimal distortion. Continue reading

Lean Alloy Steels

Rising prices of certain alloying elements such as nickel and molybdenum have driven recent work on lower priced replacements for austenitic stainless steels.
Progress has been made in finding suitable replacements but there are some key open questions remaining regarding the performance of the materials in specific applications. Continue reading

Corrosion Fatigue

Corrosion fatigue occurs through accumulated load cycling resulting in localized irreversible cyclic plastic deformation with as a result of chemical or electrochemical reactions.
Fatigue is already often described as the most common cause of engineering failure and when a corrosive environment is introduced, there are no guarantees for a safe stress range at all.

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Lean Duplex Stainless Steel

The early grades were alloys of chromium, nickel and molybdenum. Thermodynamically, because the austenite is forming from the ferrite, it is impossible for the alloy to go past the equilibrium level of austenite.
Lean Duplex Stainless Steels have many end uses in oil and gas due to their high strength and good corrosion properties. They have been used for subsea applications including flexible flowlines, umbilical tubing, subsea manifolds, water injection lines and downhole chemical injection tubing.

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