Over the past decade, global stainless steel output has been on a strong upward trend and this in turn has positive implications for the abrasives industry. In this article we take a closer look at some of the factors that have driven this demand.
What is Stainless Steel?
Stainless steel was first fabricated in 1913 by Harry Brearley. In the abrasives industry, stainless steel is sometimes referred to as inox (short form of the French word inoxydable) and is an alloy of steel with at least 10.5% chromium content. The chromium constituent is the element that gives stainless steel its characteristic durability and resistance to corrosion by producing a thin “passive” layer of oxide on its surface. The two most common grades of stainless steel used globally are 304 and 316, which represents a slightly different chemical composition; with 316 containing a greater proportion of nickel.
Stainless Steel Output
Production of stainless steel is a metal on the up and has been for some time now. In 2017 crude production of the material reached 48.1 million tonnes, which represented an increase of 5% on the previous year (2016). In 2018, output of stainless steel exceeded 50.5 million tonnes; representing a further 5% growth and thus, production has has effectively doubled over the past decade. We took a look at some of the factors which might have caused this trend and may influence output into the future.
1. Increasing global population
Perhaps the most general and largest macro-environmental factor influencing the production and utilisation of stainless steel is the ever increasing global population. Look at any man-made element of human civilisation and you will most likely find stainless steel components; as the population increases, thus the demand for these items also increases.
Stainless steel is an attractive material for construction projects due to its longevity, non-corrosion, hygienic properties, and presently its relatively low price. As the prevalence of the human race grows, as does the requirement for construction projects; hospitals, schools, airports, houses, and centres of commerce (to name a few) all of which rely heavily on the availability of stainless steel.
Due to environmental pressures, the construction industry has adopted various strategies for lowering emissions, one such strategy includes the increased usage of more sustainable materials, such as timber. Ultimately, this increase is also correlated with a rise in the production of stainless steel fixings and fastenings to secure these materials in place within the building.
In food production, stainless steel is one the most ubiquitous materials used and it absolutely critical to the operation. Milk, beer, wine and soft drinks are all prepared and stored using stainless steel equipment. Commercial kitchen surfaces, cookware, cutlery and specialised equipment are (for the most part) fabricated from stainless steel. As the population grows, it naturally follows that the requirement for food preparation will follow that upward trend and further demand for fabricated stainless steel products. To further this demand, it is perhaps relevant to note that craft beer markets in Western Europe and North America are currently booming, the catering sector is expected to show significant growth in 2019, and the food service industry as a whole recorded its ninth consecutive year of sales growth in 2018. Source: Food Service Industry Forecast 2019.
An additional consideration is the investment in infrastructure projects that governments the world-over are having to make in order to support this numerical expansion in the human populace. In the UK for example, the HS2 (High Speed 2) project is one where stainless steel components will be ubiquitous. From the exhaust systems that are fitted to the newly manufactured trains, to the internal luggage racks on the inside. Stainless steel will be required in the beading around the carriage windows and the handrails that will assist each of the projected 300,000 daily users up and down the train station steps – each item will require fabrication and finishing with abrasive products.
Finishing a stainless steel handrail
As this video on finishing a stainless steel handrail highlights, any number of different abrasives, processes and experts are required to finish one newly fabricated item before it can be used commercially. The availability of commercial steel and subsequently fabricated items is a direct influence on the abrasives industry as a whole.
More human beings require more hospitals and from the elevator wall panels to the most precise scalpel in the surgeon’s armoury, stainless steel is adopted– only in very different finishes and chemical compositions. The difference that a particular finish imparts on the properties of the metal can be drastic; this is influenced heavily by the types of abrasives used.
Driven by the ageing population particularly in the ‘baby boom’ generation, the demand for orthopaedic implants such as hip and knee replacements is expected to climb. In the USA alone, numbers recently topped out at over 1 million operations; a 3-fold increase over a 15-year period. Stainless steel is still one of the most cost effective and commonly used metals selected for hip replacements. Particularly with metal-on-metal joints, low resistance is absolutely essential to prevent the joint wearing out too quickly. Therefore, an extremely smooth surface finish is obligatory. It is a similar case in the operating theatre, where the three most common types of surgical steel are austenitic 316, martensitic 420, and martensitic 440. Austenitic 316 stainless steels contain a small molybdenum additive, which improves resistance to acidic conditions and electrolytes found in blood. The martensitic alloys are similarly resistant to blood and constituent chemicals such as ammonia and carbonic acid. To achieve the desired ultra-smooth, bacteria inhibiting surface, electropolishing is the process of choice.
2. Modern Tastes
Another potential driving force behind stainless steel output could be attributed to a change in modern tastes in design. The clean lines and pristine appearance that stainless steel provides has become fashionable and (consequently) in greater demand over the last 5 years.
Stainless steel metal cladding for buildings is being widely adopted by some of the world’s leading architects not just for the functional industrial project but also for modern, corporate building too where the material’s aesthetics are of critical importance to the client. The surface finish to this external metal cladding is, (as one architectural journal put it) “Almost as important as the selection of the metal itself” and from brushed to mirrored, Norton’s engineering abrasive products are used at the forefront of finishing for stainless steel.
Increasingly too, stainless steel is being selected by the house builder and interior designer for the residential market. Luxury apartments often feature the same glass and stainless steel look that those corporate business high rises opt for - a kind of polished ‘business chic’, urban look that has been synonymous with contemporary style for some time now. The demand for black stainless steel homeware and kitchen appliances in particular has been well established. The appeal may be obvious; in a world where people generally have less time to clean and maintain their property, and (with the rising cost of living) less money available to replace it, black stainless steel does offer a combination of enduring style, practicality and durability. The number 4 ‘brushed’ surface finish with its characteristic diagonal linear effect, is still the classic finish of choice for kitchen appliances. It is achieved with a 120-180 grit abrasive belt followed by a very fine non-woven belt, used in one direction to create the linear effect).
3. Sustainability Focus
As the world looks for a set of solutions to ease its environmental concerns and pressures, nearly all proposed technologies will, in some way depend on steel. Wind farms, solar panels, geothermal pipelines all contain a significant proportion of stainless steel components.
Stainless steel is now in fact replacing many materials in the construction of renewable energy and sustainability technologies due to its low cost, low maintenance, and end-of-life residual value – the scrap material is 100% recyclable. The durability and minimal maintenance requirements associated with stainless steel also make it a good choice from a practical perspective; particularly in the case of offshore wind farms where corrosive seawater damages most other materials and repairs are often difficult and costly to make.
As 316 stainless steel displays more corrosive resistance than the 304, it is typically utilised for this kind of application (having been utilised for many years for offshore oil rigs). The advantageous properties of 316 are derived from a higher composition of nickel, which does make it more expensive but over the lifespan of an offshore wind farm (for example), is far outweighed by reduced maintenance costs.
4. The Automotive Industry
Every year, there are more cars on the world’s roads than the preceding year with the rate of production far exceeding scrappage. As stainless steel appears (mainly) in the exhaust systems of road-faring vehicles, production of these components in automotive manufacturing is intrinsically linked to the availability and price of global stainless steel.
Car Exhaust Systems
The internal surface of a car exhaust pipe is exposed to high temperatures and corrosive gas, whilst the external side is open to road conditions and elements such moisture and salt. Stainless steel provides a cost effective and suitably inert material choice for vehicle exhaust systems. The 2 main types of stainless steel used for exhaust components are 304 and 409; again, the difference between the two lies in the chromium and nickel content. The 304 alloy contains a greater percentage of chromium and nickel, which makes it more expensive but much more resistant to rust.
Electric Vehicle Charging Stations
As the meteoric rise of the electric car shows every indication of continuing long into the future, this upsurge is correlated with the pressing need to proliferate the vast global road network with electric vehicle (EV) charging stations. To provide some perspective, the ChargePoint network is the World’s largest system of charging stations with approximately 800,000 units today. Their vision is to swell these numbers by further 5 million over the next decade. The machines that form this network are typical of those manufactured by the UK largest supplier; BP Chargemaster (alongside most other providers) - a powder coated stainless steel shell and chassis with RIM polymer panels. As such, demand for stainless steel to supply the proposed 6 million EV stations (and the abrasives required to finish it) looks set to be an area of growth for years to come.
How this all effects the world of abrasives
Stainless steel will, in almost all cases, require at least one abrasive process to finish it prior to being used in any meaningful way in the real world. For instance, every single weld made to stainless steel requires some degree of grinding down and finishing. As such, and as we have explored, this global demand for stainless steel products is likely to be a critical linchpin for our abrasive products long into the future. Furthermore, as current technologies involving stainless steel incessantly improve and new technologies are developed, so the requirement for novel and increasingly efficient abrasives will continue. At Saint-Gobain Abrasives, we take our position as a global leader and innovator in the abrasives industry very seriously and are recurrently investing heavily in developing the next generation of industry solutions.