metals that include gray, ductile, aus- tempered ductile, carbidic austempered ductile, compacted graphite, malleable, white and alloyed irons. Because of their excellent properties gr y and ductile irons
I and castabilit
are the dominant metals produced in metalcasting facilities today. Gray cast irons are the pre- ferred material when the designer is seeking low cost complex geometries with strength and high density. For applor applicications in which thermal conductivity compacted graphite
densit ations in
which thermal conductivit is needed,is needed, compacted graphite iriron (CGI) is an ideal candi- date
n (CGI) is an ideal candi- date. For higher strength ap- plications, ductile iron can be used.
plications, ductile ir n can be used. Austempering of ductile iriron creates additional oppor- tunities by further impr ving strength, fatigue resistance and wear resistance Carbidic
or higher strength ap- ustempering of ductile
n creates additional oppor- tunities by further improving strength, fatigue resistance, and wear resistance. Carbidic
Iron Alloys
ron castings are produced by a variety of molding methods and are available with a wide range of properties. Cast iron is a generic term that designates a family of
austempered ductile iron (CADI) is the next generation of austempered ductile iron ADI with higher wear resistance, making it suitable for use as digger teeth, ripper points, wear plates, rasp bars, cutters and crushers.
Properties
Because of their excellent properties and castability, gray and ductile irons are the dominant metals produced in metalcasting facilities toda Gr
T e basic strength and hardness of all irl iron alloys is provided by the metallic structures containing graphite. T e properties of the iron matrix can range from those of soft, low-carbon steel (18 ksi/124 MPa) to those of hardened, high-carbon steel (230 ksi/1,586 MPa). T e modulus of elasticity varies with the class of iron and the shape (sphericity) and volume fraction of the graphite phase (percent free carbon).
Because of their relatively high
silicon content, cast irons inher- ently resist oxidation and corrosion
by developing a tightly adher- ing oxide
and subscale to repel further attack. Iron castings are used in applications where this resistance provides long life. Resis- tance to heat, oxidation and corrosion are appreciably enhanced with alloyed irons. Properties of the cast iron family can be adjusted over a wide range and enhanced by heat treatment. Anneal- ing produces a matrix of soft machin- able ferrite In limited situations, this annealing can be accomplished at sub- critical temperatures. Heating above critical temperatures takes the carbon from the graphite and places it in the matrix. This engineered material can be through-hardened and tempered entional heat treating or able 1). These
using conventional heat treating or surface hardening (
Types ypes Gray ir ay iron—Fllake gr ake graphite provides
gray iron with unique properties (such as excellent machinability) at hardness levels that produce superior wear-resistant
y ir n with unique pr cel
dness le
oduce super ear-r har
characteristics, ties (such as
surface hardening (Table 1). These adjustments create the different mem- bers of the cast iron family.
djustments create the different mem- bers of the cast ir n famil
able ferrite. In limited situations, this annealing can be accomplished at sub- critical temperatures. Heating abo critical temperatures takes the carbo fr m the graphite and places it in the matrix. This engineered material can be through-hardened and tempered using co
The main shank of the planter row unit was converted from 17 stamped steel parts to three ductile iron castings, the no-till coulter arm was consolidated from fi ve steel parts to one casting, and the parallel arm was consolidated from seven parts to one.
2015 CASTING SOURCE DIRECTORY METAL CASTING DESIGN & PURCHASING 15
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 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131 |
Page 132 |
Page 133 |
Page 134 |
Page 135 |
Page 136 |
Page 137 |
Page 138 |
Page 139 |
Page 140 |
Page 141 |
Page 142 |
Page 143 |
Page 144 |
Page 145 |
Page 146 |
Page 147 |
Page 148 |
Page 149 |
Page 150 |
Page 151 |
Page 152 |
Page 153 |
Page 154 |
Page 155 |
Page 156 |
Page 157 |
Page 158 |
Page 159 |
Page 160 |
Page 161 |
Page 162 |
Page 163 |
Page 164 |
Page 165 |
Page 166 |
Page 167 |
Page 168 |
Page 169 |
Page 170 |
Page 171 |
Page 172