Research on the Knittability of Metallic Yarns in the Warp-knitted Mesh of a Deployable Antenna

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Knitting process parameters for HF antennas

No. of mesh reflector materials	HF-1 Mesh HF-1 yarn		HF-2 Mesh HF-2 yarn
Knitted structure	reverse locknit structure		reverse locknit structure
Chain notation	Guide Bar 1	Guide Bar 2	Guide Bar 1	Guide Bar 2
	1-0/1-2//	2-3/1-0//	1-0/1-2//	2-3/1-0//
Threading ways	Full	Full	Full	Full
Let-of amount (mm/rack)	2220	2370	2220	2690
Machine speed (mm/min)	150-300		150-300

Tensile properties of warp-knitted meshes

Specimen specifications				Fracture strength (N)	Elongation at break (%)
LF-lmesh	Vertical	100mmx30mm	Average value	23.14	35.67
			CV%	14.68	18.87
	Horizontal	100mmx48mm	Average value	17.79	96.13
			CV%	8.24	5.9
LF-2 mesh	Vertical	100mmx45mm	Average value	29.30	52.23
			CV%	6.73	7.64
	Horizontal	100mmx40mm	Average value	23.68	72.63
			CV%	3.18	12.07
HF-1 mesh	Vertical	100mmx25mm	Average value	36.16	45.23
			CV%	7.49	2.56
	Horizontal	100mmxl5mm	Average value	29.01	106.78
			CV%	7.98	2.45
HF-2 mesh	Vertical	100mmx25mm	Average value	30.4	44.40
			CV%	10.5	2.35
	Horizontal	100mmx20mm	Average value	25.93	126.10
			CV%	2.38	2.63

Specification of metallic yarns

No.	LF-1 yarn	LF-2 yarn	HF-1 yarn	HF-2 yarn
Material	Nickel-plated stainless steel wire	Gold-plated molybdenum wire	Gold-plated molybdenum wire	Molybdenum wire
Diameter of monofilament (μm)	30	27	17	16
Number of monofilaments	3	3	4	4
Yarn linear density (tex)	19.8	16.7	10.5	8.2
Twist Coefficient αt	3.7	3.4	2.7	2.4

Knitting process parameters for LF antennas

No. of mesh reflector	LF-1 mesh		LF-2 mesh
Materials	LF-1 yarn		LF-2 yarn
Knitted structure	Open atlas tricot structure		Open atlas tricot structure
Chain notation	Guide Bar 1	Guide Bar 2	Guide Bar 1	Guide Bar 2
	1-0/1-2/2-3/2-1//	2-3/2-1/1-0/1-2//	1-0/1-2/2-3/2-1//	2-3/2-1/1-0/1-2//
Threading ways	1*1*	1*1*	1*1*	1*1*
Let-of amount (mm/rack)	2330	2370	2875	2870
Machine speed (mm/min)	150-300		150-300

Yarn strength after conversion based on metallic warp-knitted meshes

Mesh No.	Number of yarns in mesh		Strength of original yarn (N)	Strength of mesh (N)	Knitted yarn strength utilization factor (%)
LF-1	Vertical	80	1.67	23.14	17.3
	Horizontal	40		17.79	26.6
LF-2	Vertical	80	3.89	29.30	9.4
	Horizontal	40		23.68	15.2
HF-1	Vertical	80	2.16	36.16	20.9
	Horizontal	40		29.01	33.6
HF-2	Vertical	80	1.85	30.4	20.5
	Horizontal	40		25.93	35.0

Fitting results of multiple linear regression

	Fitting equations	R2
Knitted yarn strength utilization factor in vertical direction y1	yl =24.022+0.22x1-987.742x2	0.998
Knitted yarn strength utilization factor in horizontal direction y2	y2=40.111+0.283x1-1672.848x2	0.998

Tensile properties of metallic yarns

No.	LF-1 yarn	LF-2 yarn	HF-1 yarn	HF-2 yarn
Breaking strength (cN)	167.1	389.4	216.6	185.8
Elongation at break (%)	23.8	1.8	2.0	1.9

Bending stiffness of metallic yarns

No.	LF-1 yarn	LF-2 yarn	HF-1 yarn	HF-2 yarn
Bending stiffness By (cN·cm2)	0.0121	0.0152	0.0039	0.0037