# Casting ingots

Cast metal stock for remelting or further working: alloy identity, piece and bundle dimensions, quality evidence, charge planning and handling boundaries.

Reviewed: 2026-11-01

Tags: materials, stock-forms, casting, procurement

## Define the intended next process

For an assumed delivery of **50 ingots at 20 kg net each**, total metal is **1,000 kg**. A **600 kg** charge uses **30 ingots**. At an assumed **96% recovery**, reconcile **576 kg recovered + 24 kg process loss + 400 kg uncharged**. Keep packaging, measured mass and actual process loss separate.

An ingot is an intermediate metal product, not a finished casting specification. Two important procurement cases need separate treatment:

| Intended use | Evidence to specify |
| --- | --- |
| Remelting into castings | Alloy chemistry, contamination limits, lot identity, charge-compatible shape and mass |
| Further working into forged products | Grade and melt route, ingot identity and geometry, and the qualified downstream forging, treatment and inspection requirements |

ASTM B179 explicitly covers commercial aluminum alloys in **ingot form for remelting** and molten form for manufacturing castings. Its general use of “ingot” includes sows, T-bars, T-ingots and pigs. These are related delivery shapes, not a declaration that every shape fits the same charging equipment. [ASTM B179-18 scope](https://store.astm.org/standards/b179)

For a different route, North American Forgemasters describes receiving steel ingots from Ellwood Quality Steels, transferring them hot under cover to its forging operation. Its steelmaking description includes bottom-pouring into tapered, fluted molds. Such an ingot is feedstock for further working; the aluminum-remelting requirements below do not automatically apply to it. [North American Forgemasters steelmaking](https://www.naforgemasters.com/capabilities/steelmaking)

Write the next process in the enquiry. “Casting ingot” alone leaves unresolved whether the purchaser wants charge metal, a forging input or a cast block for direct machining. See [Stock forms and dimensions](index.md).

## Alloy identity is separate from stock shape

An ingot shape does not establish alloy, purity, temper, recycled content or finished-part performance. ASTM B179 requires specified chemical composition and uniform quality free from dross, slag and harmful contamination. It separately directs readers to casting specifications for supplementary casting data. Do not copy a finished casting's tensile strength onto an incoming remelt-ingot record. [ASTM B179 quality and specification boundaries](https://store.astm.org/standards/b179)

Hydro's foundry-alloy brochure describes primary-aluminum-based production with customer-specific compositions. Its product table associates AlSi7Mg0.3 / EN AB-42100 with A356.2. That is a bounded supplier cross-reference: retain the complete ordered designation and agreed limits rather than replacing it with an abbreviated “356” in purchasing or charge records. [Hydro foundry-alloy brochure](https://www.hydro.com/globalassets/01-products--services/casthouse/hydro-foundry-alloys-0918.pdf)

Distinguish a named alloy from a general purity designation. The LME's **high-grade primary aluminum** contract accepts specified registered unalloyed designations, including P1020A and Al99.70; its delivery shapes include ingots, T-bars and sows. LME deliverability also requires an approved brand and approved warehousing. These exchange conditions do not make unalloyed metal equivalent to a foundry casting alloy or make every ingot commercially interchangeable. [LME aluminum physical specifications](https://www.lme.com/en/metals/non-ferrous/lme-aluminium/contract-specifications)

## Dimensions, mass and packaging

Specify dimensions that control the actual operation: maximum length, width and height; nominal piece mass and tolerance; bundle dimensions and gross mass; stacking arrangement; and required access for handling equipment. Keep net metal mass separate from packaging mass. A nominal piece mass is not a dimensional drawing, particularly for tapered or interlocking shapes.

Hydro's brochure gives **7–23 kg ingots**, depending on production source, and **700–1200 kg bundles**. These are that supplier's published ranges, not a general ingot standard, and they do not identify a single fixed piece count per bundle. Confirm the selected plant's packing drawing and weight basis before planning receipt or charging. [Hydro piece and bundle weights](https://www.hydro.com/globalassets/01-products--services/casthouse/hydro-foundry-alloys-0918.pdf)

A furnace's nominal capacity is not permission to charge any ingot below that mass. Check the actual opening, charging tool, load path and supplier-approved charging sequence. For receipt and storage, define whether a bundle remains intact, where it can be supported, and how identification survives unbundling. Use the packaging and equipment instructions for lifting and stacking; there is no universal safe stack height derived from “ingot.”

## Incoming quality and traceability

The Australian Aluminium Council explains that remelt ingots are normally sampled for chemical conformity, while mechanical and physical testing is not normally performed unless requested. It describes identifying conforming ingots by cast number and alloy. The same manual warns that separately cast test-bar properties need not represent the actual cast component. A chemistry certificate and a cast test bar therefore answer different questions. [AAC, sampling and testing, printed page 16](https://aluminium.org.au/wp-content/uploads/2025/03/250321-Al-Data-Ingots-Castings-Foundry.pdf)

If internal soundness matters for a forging input, define the qualified inspection and downstream acceptance stage with the producer. Do not transfer a remelt-ingot visual acceptance rule to a product whose internal material will remain in a finished forging. Conversely, a defect relevant to direct machining may have a different significance when the entire piece will be remelted.

## Storage and furnace-charging boundaries

For aluminum, the AAC warns that water contacting molten metal can cause a violent explosion. It identifies condensation and shrinkage voids in ingots or sows among moisture sources, calls for clean, dry storage, and requires completely dry charge material. Excessive corrosion and contamination can also introduce nonmetallic inclusions. [AAC handling and storage, printed page 11](https://aluminium.org.au/wp-content/uploads/2025/03/250321-Al-Data-Ingots-Castings-Foundry.pdf)

Treat dryness as a controlled receiving, storage and charging requirement. Do not equate an apparently dry outer surface with a qualified charging condition. Use the actual alloy supplier's current safety data and the facility's approved drying/preheating and charging procedure; this reference supplies no universal drying temperature, holding time or immersion method. Maintain alloy segregation as well as moisture control: remelting does not excuse unidentified contamination.

## Original charge-planning example

Assume a hypothetical delivery contains **50 ingots of 20 kg net each**. Total received metal is `50 × 20 = 1000 kg`; packaging is excluded. Suppose the foundry plans to charge 600 kg: `600 / 20 = 30` nominal pieces, leaving 20 pieces or 400 kg in stock.

If a separately established planning yield is **96%**, the estimated recovered metal from that charge is `600 × 0.96 = 576 kg`, with `600 − 576 = 24 kg` classified as the assumed process loss for this illustration. Reconciliation is `576 + 24 + 400 = 1000 kg`. The 96% assumption is invented for the example, not a supplier guarantee; actual mass, dross treatment, returns and process losses need their own records. This calculation neither sets the furnace's permitted charge nor predicts chemistry changes during melting.

## Source editions and order checklist

The cited ASTM listing identifies **B179-18** as active, last updated May 31, 2018. The AAC manual explicitly says **issued March 2025**. Hydro's PDF footer says **© Hydro 2019**; its “0918” filename is not sufficient to claim a September 2018 technical revision. The NAF and LME live pages show no technical edition date.

Before ordering, resolve the intended next process, full alloy/specification and edition, piece and bundle constraints, quality/certificate requirements, traceability, and handling instructions. Confirm current supplier capability and acceptance criteria at quotation. Finished-part properties remain subject to the selected casting or forging process and its own qualification.