Modelling of anisotropic elastic properties in alloy 718 built by electron beam melting

Figures & data

Figure 1. Schematic representation of the tensile test sample geometry (all dimensions are in mm). Both direction tensile specimens have the same dimensions.

Table 1. Nominal chemical composition of the raw powder.

Element	Ni	Cr	Fe	Nb	Mo	Co	Ti	Al
wt-%	Bal.	19.1	18.5	5.04	2.95	0.07	0.91	0.58
Element	Mn	Si	Cu	C	P	S	N	O
wt-%	0.05	0.13	0.1	0.035	0.004	0.001	0.0128	0.0133

Figure 2. Schematic representation of the EBM samples. Hatch planes show the planes that were used to obtain EBSD data.

Table 2. EBSD image acquisition details.

			Dimensions (µm)
Image no.	Image acquisition plane	Rough location of the image in the plane	X	Y	Z	EBSD scan step size (µm)
1	YZ (parallel to BD)	∼5 mm from bottom		2534	1434	1.5
2
3		∼12 mm from bottom		1740	2535	15
4
5
6				1739	708	1.5
7				1741	702	1
8		∼3 mm from top		984	1944	1.5
9	XY (normal to BD)	N/A	2535	1740		15
10			2535	1740
11			2535	1740
12			734	1739		1.5
13			681	1738		1
14	YZ	∼3 mm from top and 45° to BD		984	1994	1.5

Table 3. Single crystal elastic constants (units in GPa) of nickel-based superalloys and directional Young’s Modulus values (units in GPa).

Material	C11	C12	C44	E<001>	E<101>	E<111>	Reference
Ni	250.5	160.5	118.5	125.1	220.0	294.4	[26]
ALLOY 718	240.9	140.5	105.7	137.4	214.5	263.8	[27]
ALLOY 718	259.6	179.0	109.6	113.5	204.6	279.0	[28]
ALLOY 718	231.2	145.1	117.2	119.3	212.4	287.1	[29]
Average	243.9	154.9	110.8	123.6	211.4	277.1
IN600	234.6	145.4	126.2	123.3	223.0	305.3	[30]
IN625	243.3	156.7	117.8	120.5	215.3	291.7	[31]
IN738LC	235.2	147.7	122.5	121.2	218.6	298.6	[32]
IN792	263.6	172.8	123.4	126.7	226.8	307.8	[32]

Figure 3. Schematic representation of the boundary conditions used in OOF2 model.

Figure 4. EBSD invers pole figure colour maps from hatch region: (a) parallel to the build direction (BD), (b) normal to the build direction (BD), inverse pole figure maps for the EBSD image in (b).

Table 4. Predicted Young’s Modulus.

		Dimensions (µm)				Young’s Modulus (GPa)
Image no.	Image acquisition plane	X	Y	Z	EBSD scan step size (µm)	X	Y	Z
1	YZ (parallel to BD)		2534	1434	1.5			126.3
2								124.3
3			1740	2535	15			126.5
4								127.2
5								127.2
6			1739	708	1.5			126.8
7			1741	702	1			126.5
8			984	1944	1.5			125.4
9	XY (normal to BD)	2535	1740		15	172.8	169.4
10		2535	1740			167.5	167.8
11		2535	1740			163.4	163.8
12		734	1739		1.5	168.3	164.7
13		681	1738		1	166.1	163.8
14	YZ		984	1994	1.5	249.4	233.1

Figure 5. Average Young’s Modulus from Experimental and Modelling work together with reported Young’s Modulus values of EBM Alloy 718 with columnar microstructure.

Table 5. Overall elastic stiffness matrix.

Cij (GPa)	1	2	3	4	5	6
1	275.6	125.8	152.3
2	125.8	274.5	153.4
3	152.3	153.4	248.0
4				107.6
5					106.4
6						68.0

Figure 6. Young’s Modulus variation with respect to the build direction.

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