Creep-testing machine

A creep-testing machine measures the alteration of a material after it has undergone stresses. 
Engineers use Creep machines to determine the stability and behaviour of a material when put through ordinary stresses. They determine how much strain (load) an object can handle under pressure, so engineers and researchers are able to determine what materials to use. 
The device generates a creep time-dependent curve by calculating the steady rate of creep in reference to the time it takes for the material to change.
Creep.
Creep is the tendency of a material to change form over time after facing high temperature and stress. Creep increases with temperature and it is more common when a material is exposed to high temperatures for a long time or at the melting point of the material. 
Creep machines are used to understand the creep of materials and determine which type can do the job better, which is important when making and designing materials for everyday uses. They most commonly test the creep of alloys and plastics for the understanding of their properties and advantages of one material's use over another.
Background.
The first creep testing machines were created in 1948 in Britain to test materials for aircraft to see how they would stand in high altitudes, temperature and pressure. The machines were first developed to further calculate and understand the steady rate of creep in materials. 
Design.
Researchers look to test objects with a creep machine to understand the process of metallurgy and the physical mechanical properties of a metal, test the development of alloys, receive data from the loads that are derived and to find out whether a sample or material is within the boundary of what they are testing. The basic design of a creep machine is the furnace, loading device and support structure.
The main type of creep testing machine is a constant load creep testing machine. The constant load creep machine consists of a loading platform, foundation, fixture devices and furnace. The fixture devices are the grips and pull rods.
Applications.
Creep machines are most commonly used in experiments to determine how efficient and stable a material is. The machine is used by students and companies to create a creep curve on how much pressure and stress a material can handle. The machine is able to calculate the stress rate, time and pressure.
Creep testing has three different applications in the industry:
Graphing of creep.
Creep is dependent on time so the curve that the machine generates is a time vs. strain graph. The slope of a creep curve is the creep rate dε/dt The trend of the curve is an upward slope. The graphs are important to learn the trends of the alloys or materials used and by the production of the creep-time graph, it is easier to determine the better material for a specific application.
Stages of creep.
There are three stages of creep: 
By examining the three stages above, scientists are able to determine the temperature and interval in which an object will be disturbed once exposed to the load. Some materials have a very small secondary creep state and may go straight from the primary creep to the tertiary creep state. This is dependent on the properties of the material that is being tested. This is important to note because going straight to the tertiary state causes the material to break faster from its form.
A linear graph denotes that the material under stress is gradually deforming, and this would be harder to track at what level of stress an object can handle. This would also mean that the material would not have distinct stages, which would make an object's breaking point less predictable. This is a disadvantage to scientists and engineers when trying to determine the level of creep the object can handle.