Metallographic sample preparation and hardness testing are the two essential steps behind every reliable material-microstructure judgment. From cutting a part to reading its hardness number, the chain has to stay consistent, and CHENJI covers each stage on one trustworthy source. Whether you run a heat-treatment workshop, a foundry QC lab, a university materials department, or a third-party inspection institute, our sample prep machines and hardness testers are built to turn raw metal into confident, repeatable data.
Overview
Metallographic analysis is the way engineers see inside a material: it reveals grain size, phase distribution, case depth, decarburization, inclusions and heat-treatment structure. The classic workflow goes cutting, mounting, grinding and polishing, then microscopic observation — while hardness testing adds a fast, quantitative check of the mechanical condition of the same surface. Together they answer the questions that tensile or impact testing cannot: what is the material actually made of, and did the process do its job?
CHENJI delivers the full chain. Our Q-3T metallographic sample cutting machine, pre-grinding belt machines, automatic mounting machines, grinding and polishing machines and inverted metallographic microscopes prepare the surface, while the micro-Vickers, Vickers, Rockwell and Brinell series turn that prepared surface into a hardness value you can record, compare and act on.
Sample Preparation Range
The quality of a photomicrograph and a hardness indentation both depend on the surface under the tool. Every step has a dedicated CHENJI machine.
Cutting
The Q-3T metallographic sample cutting machine handles metal and non-metallic materials, and is especially kind to long tubular parts. With a spindle speed of 2800 r/min, a φ250×2×φ32 mm grinding wheel and a maximum cutting diameter of φ60 mm, it cuts samples ready for the next stage. A built-in cooling system carries away cutting heat so the microstructure is not burned or damaged. Power is three-phase 380V 50Hz from a 2.2 kW motor, and the machine weighs about 190 kg.
Pre-grinding
The D915-1 and D915-2 belt grinding machines provide fast pre-grinding and deburring before spectrometric analysis and fine polishing. The dual-belt design lets you fit two different grit belts at once for rough and fine work, saving time and consumables. Dry and wet modes are both available; in wet mode circulating cooling water protects the sample surface. A 1.1 kW motor drives the belt at 7 m/sec, with belt size 100×920 mm or 100×915 mm and a tool-free belt change.
Mounting
Small, irregular or hard-to-hold samples need mounting before grinding. The XQ-2B metallographic sample mounting machine presses specimens of φ22, φ30 or φ45 mm in thermosetting plastics, with a digital thermometer and a safety cover. For higher throughput, the fully automatic ZXQ-5 mounts two samples at the same time in φ25, φ30, φ40 or φ50 molds. Heating runs up to 180 °C with 40–90 °C cooling, pressure-hold time up to 99 min 59 s, and a system pressure setting of 0–2 MPa (0–72 MPa at the sample). Cooling is by water.
Grinding & Polishing
The P-2T is a classic single-disc polishing machine with a φ200 mm plate standard (φ230 mm custom) at 1400 r/min, letting two people work at once with single-disc control. The MPS-2B combines grinding and polishing with a φ203 mm disc standard (φ230/φ250 custom), three speed options up to stepless 0–1400 r/min, AC servo drive and a water-cooling top and dirt-flush bottom so the disc rarely blocks. The MP-2M is a double-disc touch-screen machine with frequency-converter speed control from 50 to 1000 r/min, ideal for pre-grinding, grinding and polishing in parallel workflows.
Microscopic Observation
The inverted 4XB and trinocular 4XC metallographic microscopes use an infinity chromatic-aberration-corrected optical system and professional metallographic objectives from 5X to 50X, reaching 50–500× optical magnification. Bright-field and polarized-light modes are standard, and the trinocular head drives a digital camera through JX2015 metallographic analysis software for grain grading and report output.
Hardness Testing Range
Hardness is the fastest measurable fingerprint of a heat-treatment or coating result. CHENJI covers the four mainstream scales.
Micro-Vickers & Vickers
The HVS-1000 digital micro-hardness tester measures 5–3000 HV with test forces from 0.09807 to 9.807 N (10 to 1000 gf) and a minimum detection unit of 0.5 µm; a Knoop indenter is optional. Its low-load range suits nitriding layers, thin sheets, electroplating, and case-depth measurement of carburized and decarburized layers, complying with GB/T4340.2, ISO 6507-2 and ASTM E384. The 200HVS-5 is a direct-loading combined Vickers and micro-Vickers unit covering 0.2 to 5.0 kgf at 5–3000 HV. In the standard Vickers range, the HV-10/30/50 and automatic-turret HV-10Z/30Z/50Z cover scales from HV0.3 up to HV10.0 with test forces 0.3–10 kgf, holding times 1–99 s, and a 5–3000 HV measuring range, per GB/T4340.2 and JJG151.
Rockwell & Surface Rockwell
The MHRS-150 touch-screen Rockwell tester reads on HRA, HRBW and HRC (20–88 HRA, 20–100 HRBW and 20–70 HRC) with 0.1 HR resolution and a 5.5-inch touch display for castings, forgings, steel, non-ferrous metals and carbides. The lever-loaded HR-45A surface Rockwell tester targets thin parts and treated layers, reading HR15N/HR30N/HR45N and HR15T/HR30T/HR45T with test forces 147.1, 294.2 and 441.3 N, per GB/T230.2, ISO 6508-2 and ASTM E18.
Brinell
The HBS-3000 and HB-3000B cover 8–650 HBW with test forces from 187.5 to 3000 kgf and weigh-adding or lever loading. The touch-screen electronic HB-3000C removes the loading weights for a closed-loop force-sensor system with ten test-force levels and 14 test scales (HBW2.5/62.5 up to HBW10/3000). For large parts at the workplace, the portable HBX-0.5 measures 100–400 HBS on-site with a 4.9 J impact energy and a 20× reading microscope.
Workflow
A complete metallographic examination on CHENJI equipment follows four reproducible stages:
- Cut — take a representative section with the Q-3T, keeping it cool so the structure is true.
- Mount — protect edges and hold small/irregular parts with XQ-2B or the automatic ZXQ-5.
- Grind & polish — flatten with D915 belt machines and bring the surface to a mirror finish on P-2T, MPS-2B or MP-2M.
- Observe & measure — examine grain and phases on the 4XB/4XC microscope, then quantify surface condition with the Vickers, Rockwell or Brinell series.
FAQ
What are the four steps of metallographic sample preparation?
Cutting (Q-3T sample cutting machine), mounting (XQ-2B or automatic ZXQ-5), grinding and polishing (D915 belts to P-2T, MPS-2B or MP-2M), then observation with an inverted metallographic microscope such as the 4XC. The surface must stay cool through every abrasive step so the true structure is not altered.
When should I mount a metallographic sample?
Whenever a part is small, irregular, thin, or has edges you must preserve — for example coatings, threads, or the near-surface zone of a case-hardened part. The XQ-2B presses samples in thermosetting plastic, while the automatic ZXQ-5 mounts two at once with selectable φ25–φ50 mm molds for higher throughput.
What is the difference between micro-Vickers and Vickers hardness?
Both use a diamond pyramid and report in HV. Micro-Vickers testers such as the HVS-1000 apply very low forces (10–1000 gf) suited to thin layers, electroplating and phase-specific measurement; standard Vickers machines like the HV-10/30/50 apply 0.3–10 kgf and suit bulk or slightly larger samples. Both measure 5–3000 HV.
Can I convert between Rockwell, Vickers and Brinell values?
Direct-reading digital instruments such as the HBS-3000 display the Brinell result and offer conversion to Rockwell, Vickers and tensile-strength references. For laboratory certification you should report the value on the measured scale (for example HV, HRC or HBW) exactly as tested, since conversion tables are approximations.
Which hardness tester is best for a thin or surface-treated layer?
Use a low-load instrument: either a micro-Vickers unit like the HVS-1000 or 200HVS-5 (down to 10 gf / 0.2 kgf), or the HR-45A surface Rockwell tester (HR15N to HR45T scales) for very shallow treated layers. These avoid the indenter punching through to the substrate.
Get a Quote
Tell us your material, your process and your throughput, and we will recommend the matching cutting, mounting, polishing and hardness setup — or a complete metallographic workcell. Contact CHENJI for pricing and lead time.