Charpy vs Izod tests use different specimen support arrangements. In a metal Charpy test, the specimen rests on supports; in an Izod test, one end is clamped. Retain the named method when reviewing an impact report.
For a purchase decision, check three things together: the requested method, the specimen and test conditions, and the acceptance requirement. An energy value alone does not establish that a supplier has delivered the evidence your order requires.
Three checks before accepting the report
- Match the named method and standard to the order.
- Keep specimen identity, geometry and conditions with the result.
- Apply the agreed acceptance rule to the relevant evidence.
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Check 1: Charpy vs Izod tests need their method names
The ASTM E23-25 public scope covers notched-bar impact testing of metals, including Charpy as a simple-beam method and Izod as a cantilever-beam method. It also addresses specimens, orientation and reporting.
ZwickRoell’s metal-test explanation describes Charpy specimens on supports with the notch away from the hammer. It describes Izod specimens held vertically, with the notch facing the hammer. These arrangements give the method names practical meaning.
Record the requested standard and edition exactly. A shared reference to E23 does not tell a buyer which of its methods produced the attached result.
When an offer says only “impact tested,” ask the supplier to identify the actual method. Keep that answer attached to the report rather than expanding the original wording yourself.
| Report field | Buyer review |
|---|---|
| Named method | Does the report identify Charpy or Izod as required? |
| Standard and edition | Does the actual reference match the order? |
| Specimen and conditions | Are the tested material and result basis identified? |
| Acceptance requirement | Which agreed document defines the decision? |
Use this table as a document check. The laboratory follows the applicable full test method; the table does not replace its procedure.
Check 2: keep the specimen conditions beside the result
Start with the specimen identifier and its link to the supplied stock. Read the alloy, temper, product form and delivery references in the original documents.
Ask for the specimen dimensions, notch description, orientation and test temperature recorded for the work. Preserve any explanation of a permitted alternative specimen in the report.
Separate missing information from an actual nonconformity. A short summary may omit fields that the full laboratory report contains. Request that complete report before deciding what the evidence shows.
For a comparison of two suppliers, put the fields side by side. Mark a difference visibly instead of quietly replacing one description with the other.
If the requirement cannot be fulfilled using the available stock or sampling arrangement, request a documented proposal before approving an alternative. Route that proposal to the person responsible for the material requirement.
Our aluminum material certificate guide covers the wider connection between supplied stock and its documentation. Keep that identity chain when adding a separate impact report.
Check 3: identify the acceptance basis
Find the requirement that prompted the test request. It may be in the purchase specification, an approved drawing or another controlled material document referenced by the order.
Retain the reported quantity and its unit exactly as issued. Ask the issuer to explain an unclear label rather than rewriting it into the quantity you expected.
Keep the individual results and any required summary with the original report. A supplier’s short statement that material “passes impact” should point to the relevant evidence and acceptance requirement.
If the delivered report uses a different method, obtain the responsible reviewer’s decision on that difference. Do not create a conversion or equivalence claim to close the purchasing record.
Similarly, do not turn an impact report into an unqualified statement about an assembled product’s service life. Ask for the evidence required for that separate engineering decision.
Our aluminum fracture toughness guide addresses another material-report topic. Keep each requested test and its acceptance basis identifiable in the document package.
A fictional order with a method mismatch
Illustrative document example: order C44 requests a Charpy report. The supplied attachment has “Izod” in its method field. No measured energy or material performance is assumed in this example.
The buyer records the mismatch and asks whether the attachment is the intended report. The supplier is asked to provide the correct document or a clearly identified proposal for review.
If the report header is wrong, the issuer provides a corrected, traceable revision. If the work actually used another method, the reviewer addresses that difference against the order requirement.
The purchasing record then retains the original request, the supplier’s response and the authorized disposition. A filename change would not resolve the method question.
Keep the cutting handoff connected to the material record
Where your project also needs cut aluminum stock, send the drawing revision, stock identity and finished-part requirements with the cutting inquiry.
Separate the material-evidence request from the cutting requirements. State who supplies the stock, who arranges any required testing and which documents must travel with the delivery.
If pieces must remain identifiable for later work, explain the required identification handoff before cutting starts. Ask how that requirement will be maintained through collection and packing.
Contact JiurunCut with your cutting inquiry and the relevant drawing. Include the material documentation requirement so it can be considered alongside the cutting scope.
Common buyer questions
Does “ASTM E23” mean the report must be Charpy?
No. Its public scope includes Charpy and Izod. Check which method the order requires and which method the report actually names.
Can I accept a report with the wrong method name?
Ask the issuer to clarify what was performed. Obtain the responsible reviewer’s disposition against the order before treating a different method as acceptable.
Should I compare only the energy values?
Keep the method, specimen information, conditions and reported quantity with each value. Resolve missing or different fields before using the comparison for an acceptance decision.
What should I send with a cutting request?
Send the drawing revision, stock identity, finished-part requirements and required documentation. Identify any testing scope separately so its responsibility and delivery records are clear.