Wire arc additive manufacturing using high-strength steel tubular and solid wires

Figures & data

Table 1. Chemical composition (in wt.%) of the wires and base plate.

Material	C	Mn	Si	Ni	Cr	Mo	Fe
SW	0.08	1.57	0.49	1.41	0.32	0.21	Balance
MCW	0.04	1.47	0.45	2.33	0.31	0.31	Balance
MCW-m	0.06	1.64	0.47	2.55	0.34	0.27	Balance
S355	0.24	1.6	0.55		–	–	Balance

Table 2. Different combination of Ar and CO₂ gases for single layer deposition with solid (SW) and metal-cored (MCW) wires.

	SW	MCW
Sample a	100% CO2	100% CO2
Sample b	82%Ar + 18%CO2	82%Ar + 18%CO2
Sample c	92%Ar + 8%CO2	92%Ar + 8%CO2
Sample d	100%Ar	100%Ar

Table 3. Parameters used for deposition of single-layer deposits.

Parameters	Unit	Value Range
Travel Speed	mm/s	6–12
Wire feed speed	m/min	8–11
Voltage	V	150–250
Current	A	12–20

Table 4. Welding parameters used for evaluation of silicon islands in the metal cored wire.

Position	Current (A)	Voltage (V)	Wire feed rate (m/min)
PA	250	28	7.3
PB	240	27	7.1
PF	100	14.8	2

Table 5. A Summary of tests performed to compare the standard (MCW) and the modified metal cored wire (MCW-m).

Test	MCW + As-welded	MCW-m + As welded	MCW-m + PWHT	Test temperature
Tensile	✔	✔	✔	RT
Charpy	✔	✔	✔	−40 °C and −60 °C

Figure 1. Cross-sectional profiles of single-layer deposits produced using solid wire with different combinations of Ar and CO₂ gases.

Figure 2. Cross-sectional profiles of single-layer deposits produced using metal-cored wire with different combinations of Ar and CO2 gases.

Figure 3. Silicon islands formation in the deposits produced using standard and modified metal cored wires in the horizontal position. Note the change in location and amount of silicates.

Table 6. Chemical composition (in wt.%) of the original and modified metal cored wires.

Material	C	Mn	Si	Ni	Cr	Mo	Fe
MCW	0.04	1.47	0.45	2.33	0.31	0.31	Balance
MCW-m + As-welded	0.06	1.64	0.47	2.55	0.34	0.27	Balance
MCW-m + PWHT	0.06	1.61	0.46	2.44	0.33	0.27	Balance

Table 7. Tensile and Charpy results in as-welded and after PWHT for the MCW-m and MCW wires.

	YS (MPa)	TS (MPa)	EL%	Charpy (J) @-40 °C*		Charpy (J) @-60 °C*
				Average	SD**	Average	SD**
MCW + As-deposited	801	846	20	94	6.6	71	2.0
MCW-m + As-welded	867	890	17	95	13.2	69	3.5
MCW-m + PWHT	845	854	21	31	3.4	26	5.2

*Average of three values.

**Standard deviation.