Pushing Forward in Materials Test
The conventional wisdom is that material test equipment hasn’t changed much over the years. But, you couldn’t tell that from the new releases. Many of today’s hardness testers, torque and compression machines, and other testing systems, feature advanced electronics that add functionality to the tried and true material test machine.
At the recent Quality Expo International (QEI), held April 15 to 17, a variety of new material tests machines made their debut. They ranged from the tried and true to the latest state of the art, servo electric machines with high-powered software that added functionality.
Most companies featured entry-level machines with traditional conventional weights, but many also showed models that used closed-loop load cell technology. Load cells improve repeatability and efficiency by eliminating the conventional weights, which may lead to some measurement uncertainty.
Most models viewed at QEI had built-in electronic conversion charts that allow cross referencing of hardness scales and approximating tensile strength, eliminating the need for mechanical or electronic adjustments. Also, prevalent were machines that had upper and lower limit alarms and RS232C output for documenting readings.
Most models met or exceeded American Society for Testing and Materials (ASTM) and ISO requirements and met direct NIST-traceability requirements. In addition, preset dwell times and automatic cylindrical correction for hardness value comply with ASTM E tolerances.
New to the market
- L.S. Starrett Co. (Athol, MA) introduced two bench hardness testers, the analog 3814, with dial indicator, and the digital-motorized 3816. Both units measure the full regular Rockwell scales on all types of metals and alloys. They both have a maximum test height of 6.8 inches and conform to ASTM and SAE guidelines. The minor load is 10kgf and the major load for Rockwell scales A, B and C is 60kgf, 100kgf and 150kgf respectively. They come standard with a diamond indentor, a 1/16-inch ball indentor, five test blocks, three testing tables a V-anvil, case and cover.
The model digital tester is microcomputer controlled. It features programmable scale conversions, dwell times, an automated start routine and it automatically averages samples. It also has an RS232C serial port and a mini-printer.
- Buehler(Waukegan, IL) showed recently launched testers from its all-new 5100 series of hardness testers. The full line is made up of four models of Micromet microindentation hardness testers, seven models of Macromet digital Rockwell hardness testers and two digital Macro Vickers models.
The series includes both manual and digital models and is supplied with a choice of Vickers or Knoop indenter. They have direct verification to ASTM E384, ISO 6507-2, and ISO 4546 specifications. For applications that require alternate use of Knoop and Vickers indenters, Buehler features the three objective, two indenter MICROMET 5104 model.
Test load range of 10gf-1000gf in eight steps for standard models, 1gf-2000gf test load range in thirteen steps available in extended load. All models have a 50W light source with adjustable aperture diaphragm and removable green filter to allow dual use as a basic microscope.
- The LFPlus from Ametek Test and Calibration Instruments (Largo, FL) is designed for material testing and force measurement applications up to 1 kilo Newton and can operate independently or under remote control. It uses load cells or handheld digital force gages for load measurement of ±0.5% of reading and ±0.15% of full scale. It features a test speed range of 0.05 to 1,270 millimeters per minute with accuracy better than 0.2% in the steady state. The machines have a large working space, flexible table configurations and a crosshead that isolates user controls from the testing.
In addition, the company launched the LG Series of low-capacity mechanical force gages. Testing can be done in both tensile and compression modes. Accuracy with the new gages is 0.5% of full scale. Force capacities are available up to 100 lbf and the measurement dial rotates 360 degrees.
- The TH160 portable hardness tester from Timetrade USA Inc. (Westwood, NJ) measures steel, cast steel, forged steel, CWT/ST tool steel, stainless steel, gray cast iron, nodular cast iron, cast aluminum, brass, bronze and copper. The handheld unit comes with six impact devices and the unit automatically identifies impact devices. It can work at five impact directions and converts from HL to HRC, HRB, HB, HV and HS readings. Functions include upper/lower limits setting, battery low indication and sound alarm. Users can calibrate the probes by themselves. The on-board memory stores 128 pieces of data. It includes a printer. Software for connecting with a computer will be available soon.
lDillon Quantrol (Fairmont, MN) unveiled its I-series of force stands that can be integrated to a laptop or desktop PC running Microsoft Windows. The Dillon Quantrol TC2-i and the entry-level SnapShot-i are computer controlled force test systems that combine compression, tension and flexure testing in a tabletop system.
Both systems use load cells that send test data directly to the PC via a serial port at 2,000 samples per second. The load cells, which are interchangeable, depending on users needs, range from 5N up to 2,500N-test capacity. The TC2-I system has a 2,500N capacity with an extruded column for strength of up to 20 inches of headroom. The SnapShot-I has a 1,000N capacity and up to 13 inches of headroom.
The i-software is a user-friendly graphical interface and the control panel mode is designed to resemble a traditional force gage. Users can write, modify, save and recall test programs as needed.
- The Model ESM motorized force measurement stand from Mark-10 Corp. (Hicksville, NY) can be mounted in many different configurations and has no speed variation with load because it uses a stepper motor. Maximum load is 200 pounds, and maximum travel is 13 inches. The speed adjust dial is graduated in inches per minute and millimeter per minute and its speed ranges from 0.5 to 13 inches per minute (13,330 millimeters per minute). The unit weighs 23 pounds.
- The Satec Series of single footprint hydraulic universal testing systems from Instron Corp. (Canton, MA) is available in two models. Available in DX and LX models, the testers combine the frame, hydraulic power supply, electronics, and control panel into a single machine, reducing floor space requirements by more than 60%. The DX line includes three models ranging in capacity from 150 kN to 300 kN (33,750 lbf to 135,000 lbf). These hydraulically powered load frames include two test spaces allowing tension and compression tests to be performed in separate areas. This design lets users change between tension and compression testing without having to remove heavy fixtures.
The LX models range in capacities from 150 kN to 300 kN (33,750 lbf to 135,000 lbf). Their rigid two-column load frame provides a large test space to accommodate a myriad of specimen sizes at a comfortable working height.
Instron also offers the Thermo-mechanical fatigue (TMF) system that is designed to simulate the combined effects of thermal cycling and mechanical fatigue. These fully integrated systems test materials that are used in gas, jet and steam turbines to ensure they can withstand arduous operating conditions such as emergency shutdowns and afterburner activation. To simulate material operation in this environment, the TMF systems feature induction heaters, forced cooling systems, and force and strain measurement devices.
- The FGS-250PV 500-pound motorized test stand from Nidec-Shimpo America Corp. (Itasca, IL) features fully programmable force, travel, distance and speed. Its all-steel construction makes it reliable under harsh test conditions. The stand can move a set distance from the point at which a force is detected. Because of an extended travel range, the stand can accommodate large samples and long travel requirements.
- The ECT electronic compression tester from Larson Systems Inc. (Minneapolis) is a spring tester for the shop floor. Testers are available in capacities of 0 to 110 pounds and 0 to 750 pounds. It features a cast aluminum and steel frame for durability in harsh environments, rack and pinion drive with adjustments for wear on all moving parts, hand operation to apply force and adjust length and a standard length lock to hold position.
Standard features include built-in load cell and frame deflection compensation, digital force and length display, mechanical and software overload protection to protect the tester against damage, push button force and length zeroing and NIST traceable calibration.
A back lit LED display shows length and force data and users can read length in inches or millimeters, and can select between pounds, kilograms or Newtons for force.
- Tinius Olsen (Horsham, PA) showcased its recently redesigned Super L and new T Series testing machines. For basic manual testing, the Super L models feature a portable controller and LCD that enables handheld operation at the load frame. It allows positioning of the adjustable crosshead, prior to the test, and opening and closing of the operationally hydraulically actuated grips.
A portion of the 3-line LCD reads force in either pounds, Newton, or kfg in 10-millimeter high numbers. In addition to display load, it can be optionally equipped with instrumentation and signal conditions to display position and strain values.
The Super L comes in various capacities and configurations. For most users, the standard line has a capacity from 30,000 to 400,000 lbf and for rapid sequence production testing, the models A and AF cover a capacity range of 30,000 to 200,000 lbf. For high capacity requirements, a model is available to go to more than 600,000 lbf.
- The Clark CLC-200R Rockwell-type hardness tester from Sun-Tec Corp. (Novi, MI) has a fully-automatic load cell systems. It features a direct-loading method, load cell feedback, high-speed test cycle and user-friendly interface. All Rockwell scales are accessed with one touch, and the entire test cycle is performed automatically with accurate load control using intelligent software.
- For use with universal testing machines, the Precise Digital Controller from ADMET Inc. (Norwood, MA) connects to electromechanical and hydraulic load frames and can be retrofitted to any make or model of testing machine. It is available in data acquisition or data acquisition with auto servo control. Statistics calculated include values of hi, low, mean, standard deviation and ±3 Sigma. Test results can be printed or transmitted to a computer. The controller supports QA/QC tension, compression, flexure, shear and peel tests of metal, plastics, composites, rubber, wood, paper, food, medical devices, construction materials and manufactured products.
- The Krautkramer MIC 20 from AGFA NDT Inc. (Lewistown, PA) is a two-in-one tester combining Ultrasonic Contact Impedance (UCI) and rebound test methods. The UCI method tests small and complex shaped parts comprised of fine-grained metals, while the rebound method is preferred for larger, coarse-grained forgings and castings. UCI probes are used for hardness testing of fine-grained materials having different masses and shapes or heat-treated surfaces. Rebound impact devices are used for hardness testing on large, coarse-grained components, forging and cast materials. The MIC 20 can be calibrated to various test materials and the calibration data are saved to the instrument by the user, and can be recalled in the corresponding application case by pressing a button. The MIC 20 allows a nondirectional measurement without the input of any correction factors. Besides a conventional keypad, a touch-screen is also available for the operation, which makes the input of alphanumerical data easier.
- The Series TMG Digital Torque Gauge from Imada Inc. (Northbrook, IL) features programmable high and low setpoints for go/no-go testing. The system is color-coded; orange lights up for torque measurements less than low setpoint, green for between high and low setpoint, and red for over high setpoint. It can store up to 256 values in memory, which can be displayed or transmitted using the serial output. A real-time mode can display torque transients, or the peak mode to capture the peak torque achieved during a test. Selectable measuring units of lb-in, kg-cm, or N-cm.
- New from Phase II (Carlstadt, NJ) is the Model No. PHT-2500 Portable Hardness Tester. The digital tester is a menu driven, multi-functional unit with extended memory and RS232 output capabilities. It automatically converts to Rockwell, Brinell, Vickers and Shore hardness. It is accurate to ± 0.5% and has a measuring range of 200 to 960 HL.
- The Webster Hardness Testers from Webster Instrument Inc. (Los Angeles) is a portable hardness gage that is made in three models for testing aluminum, brass, copper and mild steel. It can test extrusions, tubing and flat stock. The Model B tests the hardness of aluminum alloys from the 100 to the 7075 series. The 20 graduations on the Webster dial indicator covers the range between 25 and 110 on the Rockwell E Scale.
The Model B-I 75 Tester was developed to obtain more sensitive response to slight changes in the upper range of hardness covered by the Model B such as testing mild steel and stronger aluminum alloys. For brass, the B-75 covers the range from annealed to full-hard. The 20 graduations on the Webster dial indicator covers the range between 20 and 100 on the Rockwell B Scale. The Model BB-75 Tester is used to test the hardness of electro-deposited copper in the low hardness range.
1. Load cells are available from most companies. The load cells replace traditional conventional weight systems.
2. Software allows increased capabilities for statistical processing.
3. On most models, data can be downloaded to a computer via a RS232 or other serial port. Also, many models come available with an onboard printer.