The Direct Nickel Process

Using nitric acid as a leaching agent the direct nickel process can treat all types of nickel ore and produces a single flow sheet for a number of final saleable products.
As an atmospheric hydrometallurgical process the direct nickel process has an impressive recycle and return statistic meaning 95%+ of the nitric acid is re-used, therefore providing good environmental incentive. Continue reading

Semi-Solid Rheocasting of Alumina Alloys: Part One

Aluminum is well established at the front of the pack with regards to providing the technological answer to the increasing challenges of light weighting whilst maintaining integrity of the material for the desired applications.
Semi solid rheocasting is a development within the casting sector which enables improved quality in die casting without increasing cost. 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

Sinter Rotary Forging: Part One

Sinter rotary forging is one of the prominent sinter forming processes and uses pressed and sintered metal powder preforms as starting material. The sinter forming technique combines the advantages associated with two well-known techniques, namely powder metallurgy and conventional forming. Continue reading

Intercritical Annealing of Ductile Iron: Part One

Heat treatment can be performed on ductile iron to increase strength, wear resistance, ductility, toughness, and/or improve machinability by controlling the matrix microstructure. In F, an intercritical heat treatment starts with partial austenitization in the intercritical region where ferrite and austenite are present. The amount of austenite depends on the chemistry of the alloy and the temperature. Continue reading

Electro-Slag Welding (ESW) of Titanium Alloys: Part Two

Due to its well-known superior strength to weight ratios, titanium has become a more and more critical material choice in aerospace applications which require heavy loading.
Due to titanium’s high chemical activity welding can be a real challenge but to overcome this, new technologies are being developed which uses the slag pool and argon to shield the weld site from interstitial element contamination. Continue reading

High Entropy Alloys: Part One

High Chromium Cast Iron: Part Two

High chromium cast irons (HCCI’s) exhibit very good mechanical properties and offer benefits for a range of manufacturing applications.
One of the main flexibilities exhibited is the possibility of HCCI’s to have different matrix structures in different treatment states whether it be austenite in casting state, pearlite in annealing state, martensite in quenching state, and tempered martensite in tempering state.
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Brazing of Titanium and Titanium Alloys: Part One

Titanium and its alloys are well known for their high-strength and corrosion resistant properties but one distinct disadvantage is the challenges associated with bonding them with other materials. Brazing could provide a solution to these challenges since only the filler material is melted in the process therefore aiding dissimilar material bonding due to little or no effect on the two main subject materials. Continue reading