Cutting, mounting, grinding, polishing and hardness testing are one process, not five purchases. Where the damage is introduced, where it is removed, and which machine in the chain decides the answer.
A steel re-rolling mill in Chattogram bought a hardness tester, a microscope and a bench grinder, and could not get a repeatable case depth reading out of any of them. The instruments were sound. The problem was two steps upstream: specimens were being cut with an angle grinder and prepared on a hand held abrasive disc, so every sample carried a burnt and mechanically deformed layer many times deeper than the case they were trying to measure.
That is the whole argument for treating metallography as a chain. Each step introduces a damaged layer and the next step removes it. Break the sequence anywhere and the microscope faithfully photographs the preparation instead of the material.
Cutting is where heat enters the specimen. A wet abrasive cut-off machine floods the kerf so the cut face stays cool, and the machine is chosen by the size of what has to be cut and by how much the operator has to do.
At the bench end, the BRILLANT 230: Cut-off Machine sections samples up to 110 mm diameter with a manual wheel feed, and its aluminium body has openings on both sides so long parts can be passed straight through the cutting chamber. The Qcut 250 M: Cut-off Machine takes wheels to 250 mm with a hood that folds inwards on opening, leaving the whole chamber accessible, and a round window for watching the cut.
Automation earns its place when the material is difficult rather than when the laboratory is busy. The Qcut 250 A: Cut-off Machine adds an automatic X axis so it can run pulsed cuts and oscillation cutting on large pieces, with travel measurement monitoring the axes during setup and operation. The Qcut 350 A: Cut-off Machine handles samples to 135 mm and adds a low contact cutting function that reduces thermal load on the specimen, plus automatic touch detection and multi-position processing. Those two features are the reason a laboratory sectioning composites, coatings or electronic assemblies pays for an automatic machine.
Above that, size decides. The Qcut 500 A: Large Cut-off Machine takes components to 190 mm on a floor standing frame with automatic traverse and chop cut, and the Qcut 600 A: Large Cut-off Machine goes to 244 mm on wheels up to 600 mm, with automatic travel and cross feed so heavy parts are cut without being repositioned by hand. In the other direction the Qcut 200 A: Precision Cut-off Machine runs up to three automatic axes at a cross feed resolution of 0.001 mm, for thin sections, coatings and electronic components where the kerf has to land within a few micrometres of a feature.
One item on this part of the list looks like an accessory and is not. The Qtool Series: Quick Clamping Tools hold the specimen without slow screw adjustment between samples, and clamping is what stops the specimen shifting mid cut. A specimen that moves during the cut damages the wheel and ruins the section, so the clamping arrangement is part of the cutting process rather than an add on.
Mounting exists to make a small or awkward specimen holdable, to give the edge support that stops a coating rounding off during polishing, and to make every sample the same shape so an automatic holder can carry six of them.
Hot mounting is the standard route. The Qpress 40: Hot Mounting Press is fully hydraulic and water cooled, with heating and cooling times, temperature and pressure set on an industrial touchscreen, mould cylinders in several round and rectangular sizes, and advanced software adding one button operation and controlled fine dust extraction. The Qpress 50: Hot Mounting Press is the same family sized for larger mould diameters, using the same closure system designed to open and close cleanly over a long service life.
Heat and pressure are not always acceptable. A quenched microstructure can temper, a solder joint can reflow, a polymer can distort. That is what the Qmount: UV Mounting Device is for: it cures the embedding resin with ultraviolet light instead of heat and pressure, with cure times short compared with conventional cold mounting resins. For laboratories examining heat treatments, electronics or plastics, this is not a luxury item.
A note that matters in Bangladesh. Mounting resins and consumables are hygroscopic and they behave differently in a humid store room. Powder that has taken up moisture gives porous mounts with poor edge retention, and the fault shows up at the polishing stage as a rounded edge nobody can explain. Keep resin sealed and dated, and buy it in quantities the laboratory will use within a season rather than in the largest available drum.
This is the longest step and the one where machine choice changes the result most directly. The base machine drives the working wheel; the head carries the sample holder and applies the load. How that load is applied is the decision.
QATM build a path through this that lets a laboratory start small. The Qpol M1 / M2: Manual Grinding and Polishing Machine covers single and twin wheel manual preparation, and both accept the Qpol GO: Grinding and Polishing Head as a retrofit, so semi-automatic preparation can be added later without replacing the base machine. That is a genuinely useful upgrade route for a department that is building a laboratory over several budget years.
Fully automatic machines then scale by capacity. The Qpol GO 1 / GO 2: Grinding and Polishing Machine runs single or twin wheel in either pressure mode. The Qpol PLUS 1 / PLUS 2: Grinding and Polishing Machine uses a higher performance head, takes holders up to 185 mm in central pressure mode and prepares specimens up to 50 mm diameter, six at a time under single pressure. The Saphir 550 / Rubin 520: Grinding and Polishing Machine and the Saphir 560 / Rubin 520: Grinding and Polishing Machine pair a base unit with a preparation head so the two can be specified separately to suit throughput. The Qpol XL: Grinding and Polishing Machine takes 300 mm and 350 mm wheels with holders from 159 mm to 204 mm, and both wheel and holder speeds are variable so removal rate and surface finish can be set independently.
Two specialist machines sit around this group. The Qgrind XL: Planar Grinding Machine does the first heavy removal step with a ForceControl function that measures removal electronically, so depth ground away is reproducible rather than judged by eye. And the Qpol Vibro: Vibratory Polisher finishes surfaces with almost no residual deformation by letting the sample move under its own weight on a vibrating cloth instead of being pressed against it. If a laboratory does electron backscatter diffraction, atomic force microscopy or nanoindentation, that final step is not optional, because a deformed layer masks exactly the result those techniques are looking for.
Mechanical polishing smears soft and work hardening metals. Aluminium, copper, austenitic stainless steel and many non-ferrous alloys will look mirror bright and still carry a disturbed surface layer that the etchant then reveals as a structure that is not there.
Electrolytic preparation removes material by anodic dissolution rather than abrasion, so no mechanical damage is introduced. The Qetch 100 M: Electrolytic Polishing and Etching Machine covers this manually, and the same unit performs electrolytic etching to reveal the microstructure. The Qetch 1000: Electrolytic Polishing and Etching Machine adds programmable control of voltage, current and time, stored per material and recalled, which is what turns a technique that depends on operator judgement into one that transfers between analysts.
Etchant handling belongs in the same conversation. These are strong acids and in several cases they need extraction rather than an open bench, which makes the fume hood part of the metallography laboratory rather than an item on someone else's budget. The selection logic is set out in fume hoods and local exhaust ventilation.
The hardness tester is the end of the chain and the reason the rest of it exists. What decides which machine to buy is not the scale so much as the pattern of indents required, because indent spacing rules limit how close two indents may be placed and that limit dictates positioning accuracy.
| Requirement | Machine class | What it gives |
|---|---|---|
| Single indents, mixed methods, operator present | Manual micro hardness tester | Vickers, Knoop and Brinell with Rockwell optional, and an eight position turret carrying up to three modules and seven lenses, so it doubles as a metallurgical microscope |
| Case depth traverses and series | Automatic micro hardness tester | Motorised XY cross slide at 2 micrometre positioning accuracy, table travel extendable to 300 by 150 mm |
| Closely spaced indent series | EVO generation automatic | Positioning accuracy improved to 0.2 micrometres, which is what makes tightly spaced case depth series legitimate |
| Routine Rockwell, one part type | Compact Rockwell tester | C frame, fixed head, spindle raises the specimen, results on a 7 inch touchscreen, to DIN EN ISO 6508 and ASTM E-18 |
| Rockwell in a production line | Production Rockwell tester | Test cycle under two seconds, Siemens S7 control with a 4 inch display, results out over RS232 |
| Large or heavy components | Macro and universal testers | Test height to 395 mm on the C frame machines, or 510 mm with a 584 by 450 mm fixed table on the E series |
In the QATM range those classes are the Qness 10 / 60 M: Micro Hardness Tester, the Qness 10 / 60 A+: Micro Hardness Tester, the Qness 60 A+ EVO: Micro Hardness Tester, the Qness 150 CS: Rockwell Hardness Tester and its automatic XY slide version the Qness 150 CSA+: Rockwell Hardness Tester, the Qness 60 / 150 RCS: Rockwell Hardness Tester for line integration, and at the large end the Qness 200 CS: Macro Hardness Tester, the Qness 250 / 750 / 3000 C and CS EVO: Universal Hardness Tester covering Brinell, Vickers, Rockwell, Knoop and plastics methods in three force classes to 3000 kg, and the Qness 250 / 750 / 3000 E EVO: Macro Hardness Tester with its motorised head and extra large table. Where specimens of differing test height have to be measured in one run, the Qness 250 / 750 / 3000 A+ EVO: Fully Automated Macro Hardness Tester uses three axis control to avoid refixturing, with a Jominy sample holder available for end quench hardenability testing.
Reading the indent is a second source of variation, and it is human. Two operators measuring the same diagonal will not agree to the last micrometre, and over a long traverse that difference becomes a trend. Qpix T2 and Qpix Control2: Hardness Testing Software handles test sequence definition, indent evaluation, series and traverse programmes and documentation, and Q AI: Automatic Indent Evaluation Software is a machine learning module that evaluates indents automatically, including on the difficult surfaces where conventional edge detection struggles. For a laboratory reporting case depth to a customer, removing operator to operator variation is worth more than another decimal place on the load cell.
Weld work sits alongside hardness and is often forgotten in the equipment list. The Qeye 200 / Qeye 800: Optical Analyser and Inverse Macroscope pair assesses weld shape, penetration depth and defects on the macro section to DIN EN ISO 5817, the Qeye 200 covering the finer fields used for laser welds and electronic assemblies and the Qeye 800 the larger fields of structural steel fabrication. A fabrication shop in Bangladesh doing pressure vessel or structural work needs this more than it needs another hardness scale.
When budget arrives in tranches, the order that produces usable results earliest is not the order most laboratories choose.
The room deserves a line of its own. Sample preparation is wet, abrasive and continuous, and ordinary laboratory furniture does not last in it. The System Laboratory: Metallographic Laboratory Furniture range is specified around exactly those conditions, with 3D planning software so a layout can be reviewed before it is built. If the alternative is a wooden bench under a window, budget for the furniture and the drainage at the same time as the machines. The wider question of what a materials testing laboratory buys, and how it differs from a civil department's, is covered in strength of materials and materials testing.