Parameters analysis for low power q-switched laser cutting in singulation process of HDD manufacturing | |
| Author | Sujin Wanchat |
| Call Number | AIT Thesis no.ISE-09-29 |
| Subject(s) | Hard disks (Computer science) Cutting |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Mechatronics, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. ISE-09-29 |
| Abstract | In General during production of a Hard Disk Drive (HDD) suspension; a final process employs a traditional die cutting to separate the part from the strip level components. Nowadays, laser cutting has many benefits over the old cutting technology, and becomes a strong trend for this type of manufacturing. One significant issue which must pay high attention to is the surface roughness of cutting plane. A rough surface trends to have plenty of clinging dross, a resolidified molten metal. Clinging dross can become harmful to the HDD operation. While the HDD is working at a very high spinning speed, the read-write head may accidentally crash into fallen dross and draw the dross along the media platter; hence, the media surface is damaged and the HDD cannot operate properly anymore. Moreover, the other issue is the heat aff ected zone (HAZ) which appears around the cutting edge after cutting. The HAZ makes the workpiece become “ nonhomogeneous”. In a design process, due to the fact that simulating nonhom ogeneous material will become much more difficult than simulating homogeneous material with FEA; it is desired to keep the HAZ as small as possible. Consequently, manufacturers must try their best to reduce surface roughness and HAZ. This paper study how four main cutting parameters: beam focal spot size, pulse frequency, cutting speed, and laser power of Nd:YAG pulsed laser affect on the average surface roughness (Ra) of cutting plane and the HAZ length. The used specimens are 304 stainless steel HDD suspension of 25 μ m thickness. The 2 4 factorial designs with addition of center points are adopted to analyze the parameters. Since the available laser power is low, the numerical results demonstrate that the inte raction among beam focal spot size, pulse frequency, and laser power is the most significant interaction with positive effect for the surface roughness. Finally, the interaction among cutting speed and laser power is the most significant interaction with positive effect for the HAZ length. |
| Year | 2009 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. ISE-09-29 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Industrial Systems Engineering (DISE) |
| Academic Program/FoS | Industrial Systems Engineering (ISE) |
| Chairperson(s) | Afzulpurkar, Nitin V. |
| Examination Committee(s) | Bohez, Erik L.J.;Nattawut Thepayasuwan;Rindle, Johann |
| Scholarship Donor(s) | HDD Cluster Scholarship;RTG fellowship |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2009 |