G10 is used to give input of cutter offset data.

Runners are passages that distribute molten metal from sprue to gates or risers around cavity inside a mold.

G41 is used to give cutter offset compensation, left of part surface.

In metal casting, a basin on top of a mold that receives molten metal before it enters sprue or downgate is known as pouring basin.

G01 will give linear interpolation movement.

Caine curve is a graph between volume ratios to freezing ratio. Caine curve is used to determine exact volume for perfect freezing.

Cast iron has low range of mushy zone. Rapid cooling produces a solidified skin or shell and Lack of uniformity in grains size and distribution will cause anisotropic properties.

The necessity of machining allowance is as follows: 1. for removing surface roughness, slag, dirt and or imperfections form casting, 2. For obtaining exact dimensions on casting, 3. To achieve desired surface finish on casting.

The freezing ratio (x) of mould is defined as ratio of cooling characteristics of casting to riser:
x = \(\displaystyle\frac{(\frac{surface \,area}{volume})_{casting}}{(\frac{surface \,area}{volume})_{riser}}\)
Freezing ratio, as per given values in question, x = \(\displaystyle\frac{(\frac{surface \,area}{volume})_{casting}}{(\frac{surface \,area}{volume})_{riser}} = \frac{2}{4}\) = 0.5.

Due to fact that, powder metallurgy giving us near net shapes, thus less machining is required for final product, so less wastage of material as scrap.