Metallographic Preparation of Copper Enameled Wire

Copper enameled wire is a new type of synthetic high-performance bimetallic wire that has developed rapidly in recent years, It is a new type of pure copper core cable replacement product vigorously promoted by the country. It is widely used in communication cables, coaxial cables, radio frequency cables, data cables, computer cables, electromagnetic wires and power transmission lines and many other fields. The project has great market potential.

01 Equipment and consumables

Equipment

Trojan TableCUT-200 automatic precision cut-off machine; Trojan Alpha-600 automatic grinder&polisher; Trojan ThetaMount pressure cold mounting machine; MN 60 series microscope; Hairdryer;

Consumables

Degreasing cotton;Transparent triangle clamp; Trojan TJ2562AB epoxy resin; Trojan PL-W polishing Lubricant; Trojan SiC abrasive paper(P400;P800;P1200;P2000;P2500); Trojan SC-JP white natural silk polishing cloth(8in); Trojan Final Red-JP final precision polishing cloth(8in); Trojan 3μm polycrystalline diamond suspension; Trojan 0.05μm alumina suspension; Trojan 0.05μm non-crystallizing silica suspension

02 Sample preparation process

1-Cutting

Cut the machine with TableCUT-200 automatic precision cut-off machine.TableCUT-200 automatic precision cut-off machine

Equipment	TableCUT-200 automatic precision cut-off machine
Consumables	SiC cutting disc
Parameter	Speed:2500rpm,Feeding speed :0.2mm/s

2-Mounting

After cleaning the sample with ultrasonic waves, the sample is placed upright in a silicone mold with a transparent triangular clamp, and TJ2562AB epoxy resin is prepared in proportion to mount the sample.

3-Grinding

Grind the specimen with Alpha -600 automatic grinder&polisher, abrasive paper P400→P2500

Alpha-600 automatic grinder&polisher
metallographic abrasive paper

Equipment	Alpha-600 automatic grinder&polisher
Consumables	Abrasive paper:P400→P2500
Parameter	Upper disc:100rpm,lower disc:200rpm,same direction;pressure:15N

4-Polishing(plane polishing)

Polish the specimen with Alpha-600 automatic grinder&polisher, use SC polishing cloth with 3 μm polycrystalline diamond suspensionfor plane polishing. Note to add PL-W polishing lubricant for polishing.

SC-JP white natural silk polishing cloth
PD-W polycrystalline diamond suspension

PL-W polishing lubricant

Equipment	Alpha-600 automatic grinder&polisher
Consumables	SC polishing cloth,3μm polycrystalline diamond suspension,PL-W polishing lubricant
Parameter	Pressure:20N,same direction speed:150rpm,time:5min

4-Polishing(fine polishing)

Polish the specimen with Alpha-600 automatic grinder&polisher, use FR polishing cloth with 0.05μm alumina suspension mixed non-crystallizing silica suspension for fine polishing.(Add 25% ammonia water and 3% hydrogen peroxide to the silica suspension)

Final Red final precision polishing cloth

AO-P alumina suspension

Non-crystallizing silica

Equipment	Alpha-600 automatic grinder&polisher
Consumables	Final Red polishing cloth,0.05μm alumina suspension,0.05μm non-crystallizing suspension
Parameter	Alumina polishing:same direction speed 150rpm,time 60s;silica polishing:same direction speed 120rpm,time 120s.

5- Observation

Equipment	MN 60 series microscope
Consumables
Parameter	50×→500×

03 Analysis

Φ1.45mm- 50×

4 pictures around -200×

The preparation of enameled wire samples can be done quickly and with high quality using the Alpha-600 automatic grinder&polisher. The equipment has good reproducibility and high preparation efficiency.

The edge of the specimen mounting with epoxy resin and the enamel layer of the enameled wire are well bonded without gaps.

If only looking at the paint layer, consider whether a final silica polishing step is required depending on the desired image quality.