Thermal Processing Technology Laboratory
*Thermal and Physical Properties
1. Gleeble 3500
With the introduction of the Gleeble 3500, Dynamic Systems Inc. has once again raised the standard by which all thermal-mechanical testing machines and physical simulation systems are judged.
The Gleeble 3500 is a fully integrated digital closed loop control thermal and mechanical testing system. Easy-to-use Windows based computer software, combined with an array of powerful processors, provides an extremely user-friendly interface to create, run and analyze data from thermal-mechanical tests and physical simulation programs.
The result is a system unequaled for physical simulation and thermal-mechanical materials testing.
The direct resistance heating system of the Gleeble 3500 can heat specimens at rates of up to 10,000C/second, or can hold steady-state equilibrium temperatures. High thermal conductivity grips hold the specimen, making the Gleeble 3500 capable of high cooling rates. An optional quench system can achieve cooling rates in excess of 10,000°C/second at the specimen surface.
Thermocouples or an optional infrared pyrometer provide signals for accurate feedback control of specimen temperatures. Because of the unique high speed heating method, Gleeble systems typically can run thermal tests 3 to 10 times faster than conventional furnace equipped machines.
The Gleeble 3500 mechanical system is a complete, fully integrated hydraulic servo system capable of exerting as much as 10 tons of static force in tension or compression. Displacement rates as fast as 1000mm/second can be achieved. LVDT transducers, load cells, or non-contact laser extensometry provide feedback to insure accurate execution and repeatability of the mechanical test program.
The mechanical system allows the operator to program changes from one control mode to another during any given test. This capability provides the versatility that is necessary to simulate many thermal-mechanical processes. The program can switch between control variables at any time and as often as required during the test. Control modes that are available include stroke displacement, force, various extensometers, true stress, true strain, engineering stress, and engineering strain.
The heart of the Gleeble 3500 is the Series 3 Digital Control System. It provides all the signals necessary to control thermal and mechanical test variables simultaneously through the digital closed-loop thermal and mechanical servo systems. The Gleeble 3500 can be operated totally by computer, totally by manual control, or by any combination of computer and manual control needed to provide maximum versatility in materials testing.
The environment for computer control of the Gleeble 3500 consists of a Windows based workstation and powerful embedded processor in the control console. The Windows workstation offers a flexible industry-standard multi-tasking Graphical User Interface for creating simulation programs and analyzing the resulting data, as well as creating reports and presentations.
The embedded processor executes test and simulation programs and collects data under the control of the Windows program. This division of labor offers the full power of the workstation to the user while tests are running, enabling the operator to create new tests and analyze data while the machine is actively executing tests or physical simulations.
The Gleeble 3500 has a full set of software tools available. The operator can create tests on the workstation through a number of programming options, including QuikSim Software, a spreadsheet-like, fill-in-the-blanks software that describes each action in a test sequence in order and duration. QuikSim allows arbitrary programming of waveforms for both thermal and mechanical systems. Other options for creating more elaborate tests include Deformation Control Software and Gleeble Script Language.
In designing the operator interface for the Gleeble 3500, DSI engineers recognized that highly flexible control is essential for machine performance. Thus every aspect of the 3500 control system can be controlled via computer and set up in advance in the program. To make the system even more flexible and allow easy, convenient manual control of the system at any time, the Gleeble 3500 includes a freestanding control console with 10 Virtual Panel Meters (VPMs). Each of these VPMs includes a control knob and data readout and can be software configured to control whatever part of the system the operator requires. As a result, the operator has total flexibility in manual control of the system, yet sacrifices none of the power and convenience of computer control when that is a better option. Prewritten test programs can be run with no modifications or, if desired, the VPMs can be used to adjust the program while the test is in progress.
Once a test or simulation has been completed, the results are automatically loaded into Origin software, a powerful and flexible data analysis package included with every Gleeble 3500 System. Origin provides many built-in mathematical functions for analyzing data as well as the LabTalk language which can be used to automate the repetitive analyses tasks typical of a comprehensive simulation or testing program. Origin can be set up to load data from each test and immediately display any number of plots, allowing a quick and easy review of each test. Origin produces colorful, publication-quality graphs and charts.
(2). Applications and Features
(3) Specimens Introduction (details in pdf file)
The Gleeble System is unique in the materials field of dynamic simulation and testing. It is the only system which programs both the thermal and mechanical variables over an extremely wide range of rates. To accommodate the flow of thermal and electrical currents and at the same time provide mechanical control, the jaw system of the Gleeble may be adapted to many shapes and sizes of specimens.
The following pages detail the specimens most commonly used. These specimens may be used for a wide variety of test. Generally, longer specimens may be used up to the maximum jaw separation available. Longer free spans always result in slower beating and cooling rates. When larger cross sections are used (with free spans equal in length to several times the cross section), the input heating power required increases rapidly. Higher heating rates also increase the input power requirements.
The Gleeble 2000 is designed to handle a wide range of specimen cross sections. The smallest cross section recommended is 5mm in diameter. The largest specimen allowed is a 20mm square or 400 mm squared cross section. The Gleeble is designed for continuous testing of specimens having a cross section of 200 square millimeters. The larger specimens may be run when the power line supply voltage is 400 volts or more and Hot Jaws are used. Continuous testing of the larger specimens may require some additional maintenance of the heating system components.
Many applications require only thermal treatment of the specimens. Specimens for this type of work require only good thermal and electrical contact at the jaws. No mechanical control over the specimen is necessary. When tensile work is required, the specimen may have threads at each end to accommodate restraining nuts. Other methods of restraint have been used, such as a spring pin at each end of a sheet metal specimen. In each case the mechanical fastening must eliminate slippage in the thermal/electrical conductive part of the jaw system. Since the conductive part of the jaw is normally smooth copper alloy for maximum conduction, any slippage roughens the surface which tends to reduce conduction. When thermal/mechanical fatigue is studied, the jaw system has a particularly difficult job. The most common way of mechanically restraining a cylindrical specimen for fatigue work is through the use of a long thread on each end of the specimen. Two nuts are then threaded on to the specimen at each end. The outer surface of the end nut in each case has a taper which fits a conical jack. This is an effective means of providing a high degree of restraint for combined thermal and mechanical fatigue.
In all cases the cylindrical and flat Gleeble specimens which do not have reduced midspans rely on the thermal gradient which is present the necessary for dynamic thermal work. This results in a midspan with lower strength and a region gripped in each jaw which has higher strength. Thus, little or no elongation occurs in the conductive part of the jaw system. Where there is very little difference in strength of the midspan at the test tempeature and the material at room temperature, it may be desirable to reduce the midspan region of the specimen.
When a reduced midspan is used, the copper wedge jaws may be threaded, eliminating the need for restraining nuts. This maintains the parallel position of the wedge jaws for critical alignment. However, threaded wedge jaws generally have a shorter life than smooth wedges (used with restraining nuts).
The design of a new specimen for a particular application must take into account the thermal and mechanical treatment the specimen is to have. Any specimen which will satisfy the needs of the application may be used provided it is within the range of sizes already given.
The above discussion has been given based on the use of steel and alloys of similar electrical and thermal resistance. When materials of substantially higher conductivity are used, proper allowance in cross section and specimen length must be made. For aluminum and copper somewhat smaller cross sections and/or longer free spans are recommended. A more important factor in using high conductivity specimen material is the type of jaw material used. When aluminum or copper specimens are sued with HOT JAWS, the power requirements are greatly reduced. With HOT JAWS, aluminum bars with cross sections the same as those used for steel may be used.
New Revision For Specimens Size (Updated in January 2005)
http://www.gleeble.com/Products/gleeble3500.htm
2. X-Ray
(1)Introduction
 ARL
X'TRA powder diffractometer(pdf file) |
The ARL X'TRA XRD system offers the cost-effective solution for high
quality powder diffraction applications.
The ARL X'TRA is a new generation of powder diffraction systems from Thermo ARL. Combining 25 years of XRD experience and engineering excellence, the ARL X'TRA offers a cost effective solution for high quality powder diffraction applications in the areas of academic research, chemicals, pharmaceuticals, polymers, semiconductors, thin films, metals and minerals.
Built around a vertical theta-theta goniometer, this instrument offers the most convenient geometry for handling powder samples by facilitating the sample preparation, sample changer options and use of specialized sample holders. In order to optimize experimental conditions, the goniometer features removable dual Soller slits and continuous variable micrometer-controlled slits for adjusting the width of both the incident and diffracted beams. The X-ray optics on the ARL X'TRA goniometer ensures unsurpassed resolution in the low angle region where peaks can be observed down to 0.5°. The system's modular configuration allows the use of various sample stages to fulfill a wide range of different applications.
The ARL X'TRA can also be equipped with Thermo ARL's exclusive Peltier cooled Si(Li) solid-state detector, tuned for high count rate in order to minimize coincidence loss. Thanks to its superior resolution compared to a scintillation detector, it removes K-Beta and fluorescence radiation thus eliminating the need for filters and monochromators. Consequently, the diffraction peak intensities are substantially higher than for other available configurations.
System control for the ARL X'TRA comes from the DMSNT¿ software running under Windows NT¿ as a true multitasking 32-bit data collection and analysis package.
All in all, the ARL X'TRA represents a substantial advance in both powder XRD technology and system capabilities per investment dollar!
(2). What's X-ray diffraction systems.
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(3).Technology |
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(4).Software
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ARL
WinXRD software for XRD systems |
Thermo ARL supplies the most advanced Diffraction Management Software
package for Windows NT/2000™: WinXRD. It controls the hardware of the ARL X'TRA
diffractometer, supports various methods of data collection, and controls basic
data analysis routines - an integral part for most users.
WinXRD is a true 32-bit data collection and analysis software program. Purchasing a license for this product provides the required software packages and parallel port security device to allow execution of the WinXRD data collection and data analysis features for one computer directly connected to the diffractometer. WinXRD programs have been developed for use with Intel Processors. The following is a listing of some of the available features for WinXRD:
Thermo ARL also offers several optional add-on software packages which work with WinXRD (available at an extra cost).
(5).Reference
