# ELID Dressing Behaviors of Non-Abrasive Iron-Based Grinding Wheels
## 2 Experimental Setup  
We have employed a surface grinding machine, the MM7140 (Hangzhou Machine Tool Factory, Zhejiang, China), equipped with an ELID electrolysis system. The homemade electrolyte used is of the HDMY-50 type, diluted at a ratio of 1:50, to implement the Electric Discharge Machining (EDM) dressing of the non-abrasive iron-based grinding diamond wheel. The selected abrasive wheel is a W1.5 iron-based bond diamond wheel with a particle size of 1.5 \(\upmu\)m and a concentration of 100%. The non-abrasive wheel consists of 60-80% \(\alpha\)-Fe powder, 10-30% copper powder, 1-10% tin powder, 1-10% nickel powder, and 1-10% graphite. Bumps on the grinding diamond wheel, located near the EDM dressing cathode, were preferentially removed. The uniform distribution of electric sparks across the diamond wheel's circumference indicated that the grinding diamond wheel was dressed uniformly. The circumference of the grinding diamond wheel post-EDM dressing ranged within 0.001 mm, as measured by a dial gauge. Grinding equipment is as shown in Figure 1. (1) Firstly, place the EDM spark erosion shaping system on the workbench and adjust the discharge gap between the grinding wheel and the EDM electrode to 0.5-1 mm. Allow the grinding wheel to uniformly discharge along its entire circumference. This indicates the completion of the grinding wheel EDM spark shaping. (2) Secondly, affix a dial indicator to the workbench, align the pointer with the surface of the grinding wheel, and rotate the grinding wheel. Measure the roundness of the grinding wheel after EDM spark shaping and transfer the roundness data to the computer for storage. (3) Lastly, connect the grinding wheel to the ELID (Electrolytic In-Process Dressing) power supply for electrolysis. After electrolyzing for 50-100 min, follow step (2) to measure the roundness of the grinding wheel. After the grinding process, the mechanical properties of the oxide layer on the non-abrasive iron-based grinding diamond wheels are measured using a nanoindentation instrument. CSM instrument (Swiss CSM Instrument Company, Geneva, Switzerland), SA UNHT-type ultra-nanoindentation instrument with a displacement resolution of 0.01 nm, a maximum indentation depth of 500 \(\mu\)m, a maximum load of 500 mN, and a load resolution of 50 nN. It used a Berkovich diamond indenter. The experiment was conducted in an ultra-clean environment with a cleanliness level of 10,000, with the ambient atmosphere being air and the temperature maintained at 24 \(\pm\) 0.5 \({}^{\circ}\)C. The approach distance ranged from 1000 nm to 0.01 mm, with an approach speed of 2500 nm/min and a retract speed of 2000 nm/min. The loading time was 30 s, the unloading time was 30 s, and there was a 5 s pause between tests. The test was repeated 5 times, and the mechanical properties were calculated using the Oliver and Pharr method. ELID pre-electrolysis was conducted on the non-abrasive iron-based grinding diamond wheel for 50-100 min to observe the formation of the oxide film on the surface. When the electric current was maintained under 1-2 A, and the oxide film was uniformly generated, it signified that the ELID electrolysis of the grinding diamond wheel was complete. The roundness of the grinding diamond wheel following the electrolytic process should be less than 0.001 mm. Plate glass manufactured by China Luoyang Float Glass Group Co., Ltd., Luoyang, China, was ground using electroplated abrasive wheels, including abrasive W1.5 iron-based wheels and non-abrasive iron-based wheels. The grinding parameters were as follows: wheel speed at 1500 rpm, grinding depth ranging from 0.001 to 0.01 mm, and a feed rate between 200 and 350 mm/min. Surface roughness and microstructure were measured using an atomic force microscope, and a comparison was made between the two. The atomic force microscope is a Veeco Corporation's model multimode nanoscope 3a, operating in contact mode with a contact-based measurement method.