Fig. 6. Solidifi cation sequence for conven- tional gating is illustrated (time in minutes).
T irteen tensile test bars were
excised from the blades at locations shown in Fig. 7. T e yield strength, ultimate tensile
strength and elongation at break appear in Table 1, along with the Quality Index (Q), which represents the metallurgical quality of the alloy. T e yield strength does not vary
much around a value of 200 MPa. However, the ultimate tensile strength and elongation are higher in the thinner parts of the blade where the solidifi cation time is lower. T e qual- ity index is less than 316 MPa, the minimum value of Q required for the ASTM B26 standard tensile specimen. T is is explained by the fact that the 0.5-in. diameter standard specimen solidifi es in about one minute while the solidifi cation time in the blade var- ies from two to 20 minutes.
Heat Treatment and Modifi ed Heat Treatment
Distortion from the quenching
process was evaluated by measur- ing the shift at certain coordinates. T is distortion should be reduced as much as possible. Since the mechani- cal properties in the blades exceeded the requirements (YS ≥140 MPa, El ≥ 2%), the researchers reduced the solutionizing temperature from 1,000F (538C) to 842F (450C). T e modifi ed heat treatment
reduced distortion considerably; however, it had to be verifi ed that the mechanical properties still exceeded the minimum values specifi ed. After the modifi ed heat treatment was applied to a blade, the qual- ity index dropped by about 50 MPa, but the yield strength and elonga- tion remained above the minimum
Non-Ferrous Melting Systems Ferrous Melting Systems Precious Metal Melting Systems Specialty Applications Furnaces & Power Supplies Retrofits & Rebuilds Field Service & Coil Repair
Pillar is your partner for induction melting solutions.
For more information please contact Pillar at
800-558-7733 Pillar Induction
21905 Gateway Road Brookfield, WI 53045
www.pillar.com
262-317-5300 August 2014 MODERN CASTING | 45 With over 45 years of excellence,
Fig. 7. The sketch shows the location of test bars excised in the blade.
Induction Melting Equipment Solutions
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78