Material Testing Sample Prep Methods

Kemet Micrologue contains a number of case studies describing various Material Testing Preparation methods and the results obtained by applying these methods. It contains the conclusions of an extensive and intense work that has been conducted at the Application Lab.

Select your Material Testing Preparation process

Disclaimer: Material Testing Preparation techniques are for guidance purposes only. Kemet recommend these should be tested on non-critical samples first and offer free trials to help establish the optimum process using Kemet equipment and consumables.

Material: 3343 High Speed Steel

Results: Standard high-speed steel grade.The steel has fine and uniform carbide, high toughness and good thermoplastic. High toughness and good cutting power owing to its well-balanced alloy composition, making it suitable for a wide variety of applications. DIN 1.3343 Alloy Steel can make all sorts of general cutters, large and thermoplastic forming cutters and making wear resistance parts under high load, such as cold extrusion die etc.

The microstructure consists of undissolved excess carbides in a matrix of martensite. These carbides are probably the types M6C (where M is either molybdenum or tungsten) and vanadium carbide (VC).

Etching: 2% Nital solution

Cutting: TRENO-M cut off wheel

Mounting: ECOPRESS 102 Mounting Press with Epoxy (600811)

Mechanical Preparation: Forcipol 102 Grinding / Polishing Machine + FORCIMAT Automatic Specimen Mover

Parameter / Stage Surface Abrasive Lubricant Force per Sample, (N) Time min. Disc Speed, rpm Head Speed, rpm
Grinding Step 1 Diamond Grinding Disc 76μ Diamond Water 30 2 300 CCW 100 CW
Final Grinding Diamond Grinding Disc 15μ Diamond Water 35 4 300 CCW 100 CW
Polishing Step 1 MBL AquaPol M 3μ W9 30 4 150 CCW 50 CW
Polishing Step 2 NFC AquaPol M 1μ W9 20 2 150 CCW 50 CW
Final Polishing CHEM-H Pad COL-K(NC) Colloidal Silica 15 2 150 CCW 50 CW

Magnification: 200X

Material Testing Preparation for 3343 High Speed Steel

Material: 20MnCr5 Case hardening steel

Results: The main application areas of 20MnCr5, Gear wheels, driveline components, shafts, pins... which are required for high hardness surface and good toughness resistance. The hardened surface can be obtained according to microstructure image.

Etching: 2% Nital solution

Cutting: TRENO-M cut off wheel.

Mounting: ECOPRESS 102 Automatic Mounting Press with Epoxy (600811)

Mechanical Preparation: Forcipol 102 grinding and polishing system.

Parameter / Stage Surface Abrasive Lubricant Force per Sample, (N) Time min. Disc Speed, rpm Head Speed, rpm
Grinding Step 1 Diamond Grinding Disc 76μ Diamond Water 20 1 250 CCW 75 CW
Final Grinding Diamond Grinding Disc 15μ Diamond Water 30 3 300 CCW 100 CW
Polishing Step 1 MBL AquaPol M 3μ W9 25 4 150 CCW 50 CW
Polishing Step 2 NFC AquaPol M 1μ W9 15 2 150 CCW 50 CW
Final Polishing NSH-B AquaPol M 0.25μ W9 15 1 150 CCW 50 CW

Magnification: 100X

Material Testing Preparation for 20MnCr5 Case hardening steel

Material: AISI 1050 Steel

Results: According to microstructre analysis; pearlite (dark island) and ferrite (light backround) phases can be detected easily.

Etching: 2% Nital solution

Cutting: TRENO-M abrasive wheel

Mounting: ECOPRESS 102 Mounting Press with Epoxy (600811)

Mechanical Preparation: Forcipol 102 grinding and polishing system.

Parameter / Stage Surface Abrasive Lubricant Force per Sample, (N) Time min. Disc Speed, rpm Head Speed, rpm
Grinding Step 1 Diamond Grinding Disc 76µ Diamond Water 25 1 300 CCW 100 CW
Final Grinding Diamond Grinding Disc 15µ Diamond Water 30 2 300 CCW 100 CW
Polishing Step 1 MRE AquaPol M 6µ W9 30 2 300 CCW 75 CW
Polishing Step 2 MBL AquaPol M 3µ W9 30 2 300 CCW 75 CW
Final Polishing NFC AquaPol M 1µ W9 25 2 250 CCW 50 CW

Magnification: 100X

Material Testing Preparation for AISI 1050 Steel

Material: BRASS (CuZn39Pb3)

Results: Brasses are alloys of Copper and Zinc. They may also contain small amounts of other alloying elements to impart advantageous properties. Brasses have high corrosion resistance and high tensile strength. They are also suited to fabrication by hot forging.

Brass alloy CW614N is used for machining. It has Lead added to the composition to improve machinability.

The microstructure of the leaded brasses contain discrete lead particles primarily in the grain boundaries or inter-dendritic regions.The Lead remains insoluble in the microstructure of the brass and the soft particles act as chip breakers. Light areas are α phase Dark areas are β phase

Etching: 10% Nitric Acid Solution

Cutting: TRENO-NF cut off wheel.

Mounting: ECOPRESS 102 Mounting Press with Epoxy (600811)

Mechanical Preparation: Forcipol 202 Grinding / Polishing Machine.

Parameter / Stage Surface Abrasive Lubricant Force per Sample, (N) Time min. Disc Speed, rpm Head Speed, rpm
Grinding Step 1 Met Disc 600 Grit Water 25 1 min. or until flat 200 CCW 100 CCW
Grinding Step 2 Met Disc 1200 Grit Water 25 2 200 CCW 100 CCW
Final Grinding. Met Disc 2000 Grit Water 30 2 250 CCW 100 CCW
Polishing Step 1 MBL AquaPol M 3μ W9 20 3 200 CW 100 CCW
Final Polishing CHEM-H Pad COL-K(NC) Colloidal Silica 20 2 200 CW 50 CCW

Magnification: 200X

Material Testing Preparation for BRASS (CuZn39Pb3)

Material: Cast Iron (GG30 Lamellar)

Results: Lamellar graphite cast iron has good corrosion and abrasion resistance, lubricating effect of graphite lamellae and metal forming ability. Not suitable for thermal treatment to harden. The main application field is the production of piston rings. According to microstructre analysis; Lamellar graphite phase can be observed easily.

Etching: 2% Nital solution

Cutting: TRENO-M cut off wheel.

Mounting: ECOPRESS 102 Automatic Mounting Press with Epoxy (600811)

Mechanical Preparation: Forcipol 102 grinding nad polishing system.

Parameter / Stage Surface Abrasive Lubricant Force per Sample, (N) Time min. Disc Speed, rpm Head Speed, rpm
Grinding Step 1 Met Disc 240 Grit Water 20 1 min. or until flat 250 CCW 75 CW
Grinding Step 2 Met Disc 600 Grit Water 25 2 250 CCW 100 CW
Final Grinding Met Disc 1200 Grit Water 25 2 250 CCW 100 CW
Polishing Step 1 MBL AquaPol M 3μ W9 25 2 200 CCW 75 CW
Final Polishing NFC Alumina Suspension No.1 Water 20 2 200 CCW 50 CW

Magnification: 100X

Material Testing Preparation for Cast Iron (GG30 Lamellar)

Material: Silver

Cutting: TRENO HP cut off wheel.

Mounting: ECOPRESS 102 Automatic Mounting Press with Epoxy (600811)

Mechanical Preparation: Forcipol 202 Grinding / Polishing Machine + FORCIMAT Automatic Specimen Mover.

Parameter / Stage Surface Abrasive Lubricant Force per Sample, (N) Time min. Disc Speed, rpm Head Speed, rpm
Grinding Step 1 Met Disc 320 Grit Water 20 1 min. or until flat 250 CW 100 CW
Grinding Step 2 Met Disc 600 Grit Water 25 2 250 CW 100 CW
Final Grinding Met Disc 1200 Grit Water 20 2 250 CW 100 CW
Polishing Step 1 MRE AquaPol M 6μ W9 25 3 150 CCW 75 CW
Final Polishing NFC AquaPol M 1μ W9 20 2 150 CCW 50 CW

Magnification: 500X

Silver

Material: Ti Grade 2

Etching: Kroll's solution

Cutting: TRENO-HP cut off wheel.

Mounting: ECOPRESS 102 Mounting Press with Phenolic Carbon Conductive Resin (600176)

Mechanical Preparation: Forcipol 202 Grinding / Polishing Machine + FORCIMAT Automatic Specimen Mover.

Parameter / Stage Surface Abrasive Lubricant Force per Sample, (N) Time min. Disc Speed, rpm Head Speed, rpm
Grinding Step 1 Met Disc 240 Grit Water 10 2 min. or until flat 250 CW 100 CW
Grinding Step 2 Met Disc 600 Grit Water 10 2 250 CW 100 CW
Grinding Step 3 Met Disc 1200 Grit Water 10 2 250 CW 100 CW
Final Grinding Met Disc 2500 Grit Water 10 3 250 CW 100 CW
Polishing Step 1 MBL AquaPol M 3μ W9 35 5 150 CW 75 CCW
Final Polishing CHEM-H Pad COL-K(NC) Colloidal Silica 35 10 100 CW 50 CCW

Magnification: 200X

Material Testing Preparation for Ti Grade 2

Material: Ti6Al4V

Etching: Kroll's solution

Cutting: TRENO-HP cut off wheel.

Mounting: ECOPRESS 102 Automatic Mounting Press with Phenolic Carbon Conductive Resin (600176)

Mechanical Preparation: Forcipol 202 + FORCIMAT Automatic Specimen Mover.

Parameter / Stage Surface Abrasive Lubricant Force per Sample, (N) Time min. Disc Speed, rpm Head Speed, rpm
Grinding Step 1 Met Disc 240 Grit Water 10 until flat 250 CW 100 CCW
Grinding Step 2 Met Disc 600 Grit Water 10 2 250 CW 100 CCW
Grinding Step 3 Met Disc 1200 Grit Water 10 2 250 CW 100 CCW
Final Grinding Met Disc 2500 Grit Water 10 2 250 CW 100 CCW
Polishing Step 1 MBL AquaPol M 3μ W9 35 5 150 CW 75 CCW
Final Polishing CHEM-H Pad COL-K(NC) Colloidal Silica 35 5 100 CW 50 CCW

Magnification: 1000X

Material Testing Preparation for Ti6Al4V

Material: Ti6Al7Nb

Etching: Kroll's solution

Cutting: TRENO-HP cut-off wheel.

Mounting: ECOPRESS 102 Automatic Mounting Press with Phenolic Carbon Conductive Resin (600176)

Mechanical Preparation: Forcipol 202 grinding and polishing system.

Parameter / Stage Surface Abrasive Lubricant Force per Sample, (N) Time min. Disc Speed, rpm Head Speed, rpm
Grinding Step 1 Met Disc 240 Grit Water 10 until flat 250 CW 100 CCW
Grinding Step 2 Met Disc 600 Grit Water 10 2 250 CW 100 CCW
Grinding Step 3 Met Disc 1200 Grit Water 10 2 250 CW 100 CCW
Final Grinding Met Disc 2500 Grit Water 10 2 250 CW 100 CCW
Polishing Step 1 MBL AquaPol M 3μ W9 35 5 150 CW 75 CCW
Final Polishing CHEM-H Pad COL-K(NC) Colloidal Silica 35 5 100 CW 50 CCW

Magnification: 500X

Material Testing Preparation for Ti6Al7Nb

Material: Wood

Cutting: Diamond cut-off wheels

Mounting: Cold mounting with KEPT Epoxy Resin and Hardener Kit

Mechanical Preparation: Forcipol 202 grinding and polishing system.

Material Test Preparation for Wood

Parameter / Stage Surface Abrasive Lubricant Force per Sample, (N) Time min. Disc Speed, rpm Head Speed, rpm
Grinding Step 1 Met Disc 320 Grit Water 20 until flat 250 CW 100 CW
Grinding Step 2 Met Disc 600 Grit Water 20 1 250 CW 100 CW
Grinding Step 3 Met Disc 1200 Grit Water 20 1 250 CW 100 CW
Final Grinding Met Disc 2500 Grit Water 20 2 250 CW 100 CW
Polishing Step 1 MBL AquaPol M 3μ W9 30 5 150 CW 75 CCW
Final Polishing CHEM-H Pad COL-K(NC) Colloidal Silica 20 2 100 CW 50 CCW

Magnification: 200X

Material Testing Preparation for Wood

Material: Zircon

Mounting: ECOPRESS 102 Mounting Press with Acrylic (600810)

Mechanical Preparation: Forcipol 202 Grinding / Polishing Machine + FORCIMAT Automatic Specimen Mover.

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Parameter / Stage Surface Abrasive Lubricant Force per Sample, (N) Time min. Disc Speed, rpm Head Speed, rpm
Grinding Step 1 Met Disc 600 Grit Water 10 until flat 200 CCW 100 CW
Grinding Step 2 Met Disc 1000 Grit Water 10 2 200 CCW 100 CW
Grinding Step 3 Met Disc 2000 Grit Water 10 2 200 CCW 100 CW
Final Grinding Met Disc 4000 Grit Water 10 2 200 CCW 100 CW
Polishing Step 1 MBL AquaPol M 3μ W9 20 2 150 CCW 50 CW
Final Polishing ASR AquaPol M 1μ W9 20 2 150 CCW 50 CW

Magnification: 100X

Material Testing Preparation for Zircon

Material: AlSi8Cu3Fe

Cutting: TRENO-NF cut off wheel.

Mounting: ECOPRESS 102 Automatic Mounting Press with Epoxy (600811)

Mechanical Preparation: Forcipol 102 grinding and polishing system.

Parameter / Stage Surface Abrasive Lubricant Force per Sample, (N) Time min. Disc Speed, rpm Head Speed, rpm
Grinding Step 1 Met Disc 400 Grit Water 10 Until Flat 250 CW 100 CW
Grinding Step 2 Met Disc 800 Grit Water 10 2 250 CW 100 CW
Grinding Step 3 Met Disc 1200 Grit Water 10 2 250 CW 100 CW
Final Grinding Met Disc 2500 Grit Water 10 3 250 CW 100 CW
Polishing Step 1 MRE AquaPol M 6µ W9 20 4 150 CW 75 CCW
Final Polishing NFC AquaPol M 1µ W9 20 2 150 CW 50 CCW

Magnification: 200X

Material Testing Preparation for AlSi8Cu3Fe