HW problem

Additive Manufacturing

Problem 1

Figure 1

Consider that a Nd:YAG laser of power P = 250 W is used to irradiate commercially pure titanium (CPTi) powder (Figure 1). Laser beam diameter d =

100 µm. The typical shape of a melt pool is shown in Figure 2. The melt pool profile in 2D is shown in Figures 3 and 4. (i) If the melting temperature of Ti64 is 1650oC, use Rosenthal’s solution to find the melt pool dimensions a, b, c, and d at scan speeds of v = 100 mm/s, 150 mm/s, and 200 mm/s. (ii) Plot melt pool width (2c), depth (d) and length (a+b) vs. laser energy density (P/v). (iii) Compare your results with the results reported in

(This problem needs Matlab Code)

“Effect of Laser Power and Scan Speed on

Melt Pool Characteristics of Commercially Pure Titanium (CP-Ti),” Journal of Materials

Engineering and Performance, 2017 (DOI: 10.1007/s11665-017-2768-6)

Figure 2 – Typical shape of a melt pool.

Problem 2

Consider that you have one FDM polymer printer and one nozzle dispensing direct write (DW) printer. You are to create embedded chip capacitor with conductive traces as shown by indicator (2) in figure below. Explain briefly the step-by-step procedure of completing the entire packaging process with schematics. You should start from the bottom and buid in the upward direction.