In terms of engine development leading materials development, modern gas turbines are an excellent example. Since the days of Sir Frank Whittle, these engines have been able to progress only through parallel development of materials that are capable of operating at ever-increasing temperatures and at higher levels of stress.
Such high-temperature materials are not just fancy Read more…
Titanium is banned in the current Formula One engine regulations from being used for threaded fasteners, despite its attractive attributes for such components. The rules specify that threaded fasteners must be made from alloys based on one of three elements - iron, cobalt or nickel - and this is planned to be carried forward for the new V6 turbo engines we will see in use from 2014 onwards. It should be noted though that there is no similar regulation governing the use of titanium fasteners on the chassis. Read more…
Despite not being fettered by overbearing regulation, the use of aluminium in the production engine remains popular because the material has much merit. While there are many production applications where lower-density materials such as magnesium or non-metallics are becoming more popular, the position of aluminium in racing is assured as there are many race series that mandate its use for certain applications. Read more…
There are a wide range of metals used in the modern race engine. Where regulations are sufficiently liberal, we may find an engine containing everything from aluminium, magnesium and steel to titanium and tungsten. In many ways the materials behave very differently but in others their specific properties, especially specific modulus (elastic modulus divided by density), are very similar. For example, a typical aluminium alloy has a modulus of 70 GPa and a density of 2.7 g/cc, giving a specific stiffness of 25.9 GPa/(g/cc). If we repeat the exercise with steel, magnesium and titanium, we find very similar answers. Read more…
The use of tungsten in motor racing is widespread, especially on the chassis side of the business, where its high density makes the material prized for use as chassis ballast. Commonly cars are designed and made underweight compared to the regulations in force, and are then ballasted to meet the minimum mass. Such is the effectiveness of achieving the correct weight distribution that cars are often designed to be well underweight, and a surprisingly large proportion of their mass is carried as tungsten ballast, as close to the lowest point of the car as possible. Read more…
The applications of copper alloys in engines are generally those where we might expect to see relative movement or where a combination of strength, wear resistance and thermal conductivity is required. A favourite type for many of these applications are the copper-beryllium alloys.
Beryllium is a very lightweight element, and has some attractive mechanical and physical properties. However, there are health considerations regarding its use. Read more…
There is little doubt that, in many ways, steels have improved markedly in recent years. Fatigue properties in particular have seen a large improvement owing to better steel cleanliness. However, it is not only the cleanliness that affects fatigue behaviour, but the processing of the steel, and this processing introduces anisotropy into the steel. Anisotropy is the effect whereby mechanical properties vary according to the direction in which they are measured.
Having seen the extremely brisk pace of development in rapid prototyping methods over the past decade, it strikes me that this is a technology that stands to revolutionise the way we will come to make many parts for race engines.
For a number of years there have been rapid prototype parts run on racecars on everything from Formula Student to Formula One. The method offers a way to have small numbers of complex parts made quickly and in Read more…
In a four-stroke race engine, the valve seats play an important part in the mechanical reliability and heat management of the valves. In general, the valve seat will conduct much of the heat away from the valve head during the time the valve is shut. If we leave mechanical and dimensional considerations aside, a valve seat material with greater thermal conductivity will transfer heat from the valve to the cylinder head, and thence to the cooling water circuit, more efficiently than one of lower thermal conductivity. Read more…
My previous article on titanium alloys looked at the possible benefits that Ti10-2-3 - an alloy containing 10% vanadium, 2% iron and 3% aluminium - might offer compared to the widely used Ti6-4 material. Ti10-2-3 has found wide use on military and civilian aircraft, commonly in structures where steel has traditionally been the material of choice. As in motor racing, there is a great advantage to be had in the aerospace industry in terms of mass reduction. Read more…
