Life's a pitch: Research 2

Metal research
In order to further investigate the materials we want to use within the wayfinding brief, we extended a line of contact to a metallurgist (Jeremy Bell) at B. Mason's, based in Birmingham. Callum has family friends working for this company so was able to contact them to find out more about the different types of metal that we could use. 

B Mason & Sons Ltd is a leading supplier of copper alloy strip, combining state-of-the-art manufacturing equipment and practices with over 160 years of experience and heritage. Our Company has progressed from a small, family run business at its inception in 1852 to becoming the UK's largest and most up-to-date manufacturer of precision strip, with a prestigious worldwide customer base.
Our focus on quality enables us to supply the most demanding markets in the UK, Europe and the rest of the world. Internal systems guarantee compliance to relevant external regulations and ensure that our products consistently exceed our customers’ expectations. We continually develop our product range and manufacturing processes to remain at the forefront of copper-based alloy technology.

Questions and Answers:

What is the most sustainable and accessible metal? 

Steel would be one answer because of its wide spread use in a range of products and applications. The majority of steel is collected an recycled (e.g. end-of-life body-in white goods [such as washing machines, cookers, dishwashers and others domestic appliances] and end-of-life vehicles). This type of steel is referred to as secondary steel as it is recovered and recycled.  Electricity is the main source of energy used to melt and process the material.  With various steel grades sorted, there is the minimum amount of additions made to produce a particular alloy type/grade. 

Primary steel in comparison is produced from iron ore, coke and other additions (such as limestone) in a blast furnace. This material undergoes various other processing stages and allotting additions to produce the desired alloy grade. This type of production route is energy and resource intensive.  

There are other types of metal, their abundance depends upon the amount of the metal element present in the ore or mineral mined. The accessibility can be accounted for in the mining (e.g. open cast, deep mining) and extraction route used (the grinding and chemical extraction/refining methods).  

For most engineering applications, the metal is alloyed with other metals or elements to increase the mechanical strength and durability of the metal product.  

What is the cheapest metal?

The cheapest metal depends on the relative abundance of the element, the cost of the element on the trading market (such as the London Metal Exchange). These trading markets control the market price  based on factors such as availability and demand. This does not fully account for countries which may control the amount of metal entering the market and directly influence the market price.  Certain countries who control the mining, extraction and refining of certain metals, designate these metals as strategic resources and control this commodity accordingly. There are ethical considerations to be made, where certain metals are mined, extracted and refined in regions of the world designated as “conflict” areas. The trading markets attempt to police and monitor which resources/metals enter the global market and ensure ethical trading occurs. 

What is the most durable? 

This depends upon the definition of durability (e.g. toughness, fatigue resistance, corrosion resistance, etc.).  Again, steel is the most durable as it can be easily alloyed to produce desired properties. For example, the addition of chromium to steel to produce stainless steel (which the discovery was by a chance observation that this material did not tarnish or undergo significant corrosion). 

It is possible to print onto metal? 

Yes, it is possible to print onto metal but this depends on the chemical nature of the metal and subsequent surface preparation, cleanliness and chemical coating/treatment of the metal surface.  Certain metals are “noble” and make the use of chemical treatment to prepare the surface for printing (Noble metals have a full valence shell of electrons, which inhibits chemical  reactions – such as oxidation, reduction and corrosion). 

Steel (as with most metals) requires a surface treatment to remove any oxide or surface corrosion. Once cleaned, the surface needs protection or priming to accept a coating or print onto the surface. One effective way to print directly onto a metal surface is to produce a “mask” and then selectively remove areas for coating.  

Another way to print onto a prepared surface is by a dry film transfer. The dry film can be heated to bond onto the surface.  

Any surface preparation (e.g. grit blasting or chemical etching) needs to cleaned (e.g. air blast, solvent rinsing and evaporation or water washing/rinsing and drying). This would involve multiple steps, in which the waste by-products can be collected and sorted for reuse.    

What metal is best to cut and weld (or what could you do to a metal before doing these processes to make it most economical and accessible)? 

There are several methods available to make precision cuts  – abrasive water jet cutting, laser cutting and wire discharge machining. There are limitations to the thickness of sheet material that can be cut, but all methods benefit from using computer numerical control (CNC). This allows a complex shape of pattern to be programmed and cut into the sheet to produce any shape or template. The water jet cutting would more environmentally friendly as the fluid can be recovered and recycled. The advent of solid state lasers allow high precision cutting of thin sheet material. These laser types are more energy efficient compared with the gas laser systems. Wire discharge machining uses an electrochemical bath and a wire electrode to cut, profile or shape.  The metal needs to be conductive as it forms the counter electrode. 

Traditional cutting involves using a tool to cut the material (which is made from an alloyed steel of high hardness or hard carbide material with a CVD or PVD coating to improve cutting performance).  

Steel is the best to weld (but  does involve surface preparation and cleanliness requirements to ensure good weld integrity). Solid state lasers are being used as they can be precisely controlled and use significantly less gas and electricity in their operation.

Typefaces in use - wayfinding 
Flama
Din 
Carbon