Inoculants

INOCULATION

STRONTIUM, BARIUM, ZIRCONIUM & CERIUM BASED INOCULANT

NPPL INOCULANTS FOR FERROUS FOUNDRIES

The term “Inoculation” refers to the introduction of Nuclei into the melt to influence structural formation of the molten Cast Iron during solidification. As per the Oxide- Nucleation theory, certain elements like Ba,Sr,Ca,Zr, & Ce; Al which have high affinity towards oxygen, are introduced in combination with FeSi as ‘Inoculants’ into The melt – they combine with oxygen present in melt & produce numerous small Nuclei (tiny particles which are <4μm in size). These Nuclei serve as Crystallization centers, where The graphite present in the melt can grow onto these nuclei. (Graphite precipitation) & form Nodules. Hence effective inoculation leads To uniform mechanical material properties in different wall thicknesses.

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Eutectic Equilibrium CONDITION

The molten cast iron which contains about 1.5 To 3% Si & 2-4% Carbon, during cooling after a certain time attains the Eutectic Composition (4.30% carbon) & then the eutectic solidification begins immediately – under Ideal Conditions, where The precipitating carbon is fully present as Graphite. Practically the Equilibrium conditions are never achieved, due To various reasons like variation in chemical compositions, wall thickness, pouring temperature, cooling speed which results in melt cooling below eutectic temperature before solidification of The eutectic begins. The purpose of inoculation now is to ensure that sufficient Nuclei are present for Crystallization of Graphite at the beginning of this Eutectic Solidification. This prevents formation of iron carbide (Fe3c) & enables formation Of evenly distributed A- Graphite (Lamellar Graphite) with formation of many small Graphite nodules in Mg treated Cast Iron.

INOCULANTS NPPL PRODUCES : FeSiBa ; FeSiCa ; FeSiSr ; FeSiRe

Pre- Conditioning:
This basically refers to reduction of oxygen content and improvement in nucleation distribution of the melt by addition of pre-conditioning agents like ZrMn & Ce along with Si, in the furnace itself during preparation of the melt or even during tapping, thereby preparing the melt for the next stage of treatment, ensuring presence of sufficient Nuclei & Nodules even before Mg treatment begins.

Pre - Conditioners NPPL Produces : FeSiZrSr ; FeSiZrMn ; FeSiSr ; FeSiZrAI

Fading Effect :
Re- oxidation & Dissolution of Nuclei leads to reduction in the number of Nodules. Inoculation treatment effect depends on Temperature & largely on Time,

as the fading begins with addition of Inoculants & ends when the Eutectic Solidification temperature is reached.
The difference in solidification times (Crystallization) for a casting with thin wall of 5 to 50 mm and that of a thick section (60mm & above) is huge, & entails a greater fading effect. Thereby leading to Longer Crystallization time with reduced number of Nodules & Bigger Size Nodules in thicker section of the casting. This Phenomenon can be Overcome by late inoculation or with Stronger Inoculant. Note Stronger Inoculant can fade away equally strongly with time.

FERRO SILICON MAGNESIUM

Ferro Silicon Magnesium Alloy imparts the correct Graphite Structure required in S.G.Iron thereby improving the Tensile Strength & its elongation properties. We produce Ferro Silicon Magnesium in wide range of specifications & combinations of Magnesium, Calcium & Rare Earth. With bare minimum inclusions of Dross & Oxides, our material reduces Alloy consumption by giving maximum recoveries with reduced fume generations.

Stringent control of Chemistry and size is ensured by offering tailored specifications & size requirements for all applications processes such as In‐Mould, Tundish or Sandwich.

Other Specifications

  • Size: Our regular sizes are 1‐5 mm, 5‐15mm, 5‐25mm and tailor made sizes can be produced on demand.
  • Packing: In Jumbo Bags or 50 kg Gunny Bags

Grade Table

STANDARD GRADES SI CA BA SR ZR TRE MN AL FE
Barium Inoculants 68-72% 1-2% 2-3% Nil Nil Nil Nil 1% Balance
Barium(H) Inoculants 60-65% 1-2% 7-11% Nil Nil Nil Nil 1% Balance
Strontium Inoculants 72-76% 0.10% Nil 0.8-1.20% Nil Nil Nil 0.50% Balance
Strontium Zirconium Inoculants 72-76% 0.10% Nil 0.8-1.10% 0.8-1.20% Nil Nil 0.50% Balance
Zirconium Alumium Inoculants 60-65% 0.5-1.60% Nil Nil 3-5% Nil Nil 3.5% Balance
Cerium Inoculants 60-65% 0.7-1.20% Nil Nil Nil 5-7% Nil 1% Balance
Zircon Manganese Inoculants 60-65% 0.5-1.60% Nil Nil 3-5% Nil 3-4% 0.5-1.50% Balance

(Other grades available & can be manufactured as per specific requirements & applications) 

STANDARD GRADESSICABASRZRTREMNALFE
Barium Inoculants68-72%1-2%2-3%NilNilNilNil1%Balance
Barium(H) Inoculants60-65%1-2%7-11%NilNilNilNil1%Balance
Strontium Inoculants72-76%0-10%Nil0.8-1.20%NilNilNil0.50%Balance
Strontium Zirconium Inoculants72-76%0.10%Nil0.8-1.10%0.8-1.20%NilNil0.50%Balance
Zirconium Aluminum Inoculants60-65%0.5-1.60%NilNil3-5%NilNil3-5%Balance
Cerium Inoculants60-65%0.7-1.20%NilNilNil5-7%Nil1%Balance
Zircon Manganese Inoculants660-65%0.5-1.60%NilNil3-5%Nil3-4%0.5-1.50%Balance

Standard Sizes:

  • 0.2 To 0.70 Mm
  • 1.0 To 3.00 Mm
  • 2.0 To 6.00 Mm
  • 3.0 To 12.00 Mm

Standard Packing:

  • 25 Kg Paper Bags On Pallets.
  • 250 Kg Steel Drums On Pallets.
  • 1250 Kg Jumbo Bags On Pallets.

Other Chemical Analysis; Refined Quality & Size Available