iaimppp gleeble

Gleeble 

 

In September 2003, one of Poland’s most cutting edge laboratories for mechanical properties research and physical simulation of metallurgical processes was launched. The laboratory is equipped with a system for physical modelling of metallurgical processes GLEEBLE 3500, produced by an American company Dynamic Systems Inc. It’s a device that enables conducting physical simulations for processes such as: continuous casting of steel, rolling, drawing, forging, extrusion, and welding. The system also allows to conduct research on plastic properties of materials for plastic working processes, structural research on plastic deformation mechanisms, and to determine material characteristics. Here are the basic technical parameters of the device: sample heating rate: 10000 °C/s, max. pressure force: 100kN, max. speed of the mobile jaw: 1000 mm/s. All trials can be conducted in lower pressure conditions or protective atmosphere. The device can be utilised in research conducted by employees dealing with plastic working processes, metallurgy workers dealing with extraction and recirculation of metals, as well as materials engineering teams. The biggest advantage of this workstation is its versatility and the possibility of adjusting to different metallurgy research.  

The basic scope of usage of the simulator:

  • developing new technologies of rolling in continuous systems
  • normalizing rolling technologies
  • thermomechanical rolling technologies
  • continuous casting technologies
  • analysing thermomechanical properties of new materials
  • determining the influence of plastic working on the internal structure and strength of materials

 

The device is especially useful in case of scientific researches requiring determination of mechanical properties of a material and describing it in an analytical way. The generated models are then used for computer simulations of actual processes. Moreover, the workstation enables modelling of mechanical properties of finished products from new materials or based on new thermomechanical working technologies.

 

The GLEEBLE system has many unique features that are not available in any other material testing machine. All the advantages together create a system with unparalleled possibilities regarding simulation processes and material study. Here are a few of its key features:

- Very fast cooling

- Freezing of microstructure

The equipment for fast cooling is placed directly inside the machine. For that reason, it is not necessary to move the heating furnace or removing a sample for cooling down. Moreover, thermocouples remain connected to the sample during cooling. Thanks to that, the operator knows the exact temperature on the surface of the sample during cooling.

- Productivity

Comparing the heating instrumentation of the tool for hot heading trials with the GLEEBLE system, the most important advantage of the GLEEBLE simulator is its high productivity. In case of a hot drawing trial, the system can conduct 4 tests per hour. In case of typical devices equipped with heaters, only one trial per 3÷4 hours is possible. Therefore, GLEEBLE’s productivity might be 12÷16 times better compared to devices with heaters. Comparing heading tests, GLEEBLE allows for 3÷10 trials in the same time the machines with heaters need to conduct one trial.

- Isothermal planes

One of the most important technical issues in case of thermal and thermomechanical measuring machines is temperature distribution in an analysed sample. It has to be checked in two conditions: static and dynamic. In static conditions, it is quite easy to obtain consistent temperature with the use of a heater or induction heating, but usually in real conditions there are no static phenomena. The temperature in hot feedstock, tank, or ingot is always changeable. The way it’s changing is a critical parameter for proper modelling of the process. During induction heating and cooling with atomised liquid, the heat is added up and taken away by the surface of a sample. The measurement takes place on the surface as well, therefore the temperature inside the sample might be behind or ahead of the actual value provided by the programme even by several hundred degrees, depending on the heating or cooling speed. The temperature might finally reach balance, but it might happen a few minutes after the surface reached the required temperature. With the use of GLEEBLE’s heating system, the core and the surface of a sample have the same temperature during hating up and cooling down (unless cooling with atomised liquid on the surface was applied). Therefore, if a sample is heated up to 1000°C in 3 seconds, the core also reaches 1000°C in 3 seconds. During induction heating the system can notify about reaching 1000°C a few minutes before the core actually reaches the temperature, depending on sample measurements. During cooling the GLEEBLE simulator receives heat through the ends of a sample, therefore the surface and the core have the same temperature. It generates transverse ISOTHERMAL planes in a sample during fast heating and cooling. The importance of the issue can be seen on the example of critical application - Continuous Cooling Transformation (CCT). In case of using bars with the diameter of 6, 10 and 12 mm in a device with induction heating (or cooling with atomised liquid) in the CCT programme for cooling at the same speed for each of the three diameters, we will obtain different transformation temperatures for each diameter, which proves that there was an evident mistake in the measuring method or the experiment. Conducting the same trial with GLEEBLE, we will obtain identical temperatures, as they should be, regardless the diameter. It is caused by the existence of isothermal planes.

- Dynamic temperature control

The GLEEBLE system provides the possibility of dynamic heating and cooling at high speeds. For HAZ (HEAT-AFFECTED-ZONE) simulations (welding processes) high speeds are of the greatest importance. For precise control over the system, it should have the possibility of adding and taking away the heat at much greater speed than required for simulation. With the possibility of heating at the speed exceeding 10000°C/s, GLEEBLE can easily and precisely control the speed of heating and cooling. Considering the entry power limits, heating and cooling with the use of induction systems are limited as well.

- Possibility of very fast heating

The GLEEBLE simulator enables heating of samples at the speed of over 10000°C/s with precise computer control and maintaining stable temperature balance. Such heating speed is obtained for carbon steel bars with the diameter of 6 mm and the length of 15 mm, with 3-phase power source of 360V and drain rate of 200A.

- Possibility of very fast cooling

GLEEBLE’s cooling speeds are controlled by conductivity. The controlled cooling rate depends on the size, shape and temperature of a sample. At the temperature of 1000°C cooling speed of 140°C/s can be obtained for a carbon steel bar with the diameter of 6 mm. The heating system enables smooth transition from the state of thermal balance to maximum cooling speed for a specific sample size and type (acc. to specification). For very fast cooling processes, an external cooling system can be applied, which enables obtaining the speed of over 10000°C/s on the surface of a sample (in case of flat samples that are 1 mm thick).

- Selection of different temperature control methods

The source of feedback signal for temperature control can be thermocouples or optional infrared pyrometer. Thermocouples are automatically linearized. GLEEBLE is equipped with one Cr-Al thermocouple channel (Type K) and one Platyna-Platynorod channel (Type S, 10% or Type R, 13%) as standard accessory. Other linearizations are also possible. The optional system of pyrometer control enables measuring the temperature without contact on the surface of a sample in cases when application of thermocouple is inconvenient or impractical.

- Areas of consistent temperature

GLEEBLE also generates an area of consistent temperature inside a sample through application of hot jaws made of corrosion-proof steel in the grips. Such area of stable temperature can be evened out on the length depending on trial requirements. For example, in a round carbon steel bar with the diameter of 10 mm and the length of about 50 mm, the central part of sample that is 7 mm long has the temperature of about ±0.5% of the average temperature value for this area.

- Horizontal placement of a strained element

GLEEBLE is based on a horizontal design. A sample is placed horizontally. It has a lot of advantages. A heated sample doesn’t cause the stack effect, as it often happens in case of vertical machines. The upper end of a sample has higher temperature then, due to the fact that the sample is heating itself. GLEEBLE eliminated this problem by horizontal sample placement. Additionally, the trial is not interrupted by the weight of the upper jaw.

- Significant variability of sample sizes and shapes

GLEEBLE is characterised by flexible jaw system, which enables utilisation of different grips for many sample sizes. There are over 20 different sample configurations available for GLEEBLE. After combining them with different sample sizes, it provides over 50 different shape and size combinations that can be analysed in this machine. It gives the freedom to choose the right sample for a particular simulation or a mechanical test, which makes the machine more flexible regarding utilisation.

GLEEBLE 3800 has many unique features that are not available in any other material testing machine. All the advantages create a system with unequalled possibilities within the scope of process simulations and material studies. The architecture of GLEEBLE 3800 is a module system. Such system enables flexibility in configuration of the device, depending on the researcher’s needs.

Key elements of the GLEEBLE 3800 system:

Basic elements:

• Stationary computer
• Industrial computer

Ancillary facilities:

  • System for cooling and filtration of water
  • Negative pressure station
  • Pneumatic system

 

Modules:

  • PocketJaw Module
  • Hydrawedge Module
  • MaxStrain Module
  • Torsion Module

Module description

 

Additional devices:

• Transverse strain measurement sensor
• Longitudinal strain measurement sensor
• Rapid cooling system – outside
• Rapid cooling system – inside
• Thermocouple welder

 

Specialized software:

• QuikSim programme – Gleeble System
• Standard software package for processing research results- Origin

 

 

More info:

PRZYCISK GLEEBLE-EN

Gleeble3

 


Laboratory supervisor: PhD, Eng. Sylwester Sawicki

Phone: +48 343250-778  

E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.