# UNS C36000 brass

Specify free-cutting leaded brass by product form, temper and acceptance limits; distinguish machining performance from corrosion and compliance suitability.

Reviewed: 2026-11-01

Tags: materials, brass, copper-alloys, machining

## Identify the alloy and supplied product

For a nominal **0.7500 in C36000 round**, Wieland Chase's **±0.0020 in** tolerance for **over 0.500 through 1.000 in** gives **0.7480–0.7520 in (about 18.999–19.101 mm)**. The smallest permitted diameter is already below a **19.00 mm** finish, so this stock size cannot guarantee positive cleanup. Allow for straightness and surface removal as well as diameter. [Wieland Chase round-bar tolerance table](https://wieland-chase.com/wp-content/uploads/2024/01/WC-Alloy-Sell-Sheet-C36000.pdf)

**UNS C36000** is a leaded, free-cutting brass used for machined components and high-volume screw-machine production. Mueller Brass lists **60.0–63.0% copper, 2.5–3.0% lead, iron ≤0.35%, and zinc remainder**. The grade is not lead-free, and the copper/zinc/lead balance is part of its machining behavior rather than a trace-contamination description. [Mueller C36000](https://muellerbrass.com/products/c36000/)

Mueller and Wieland Chase list **ASTM B16** for their free-cutting products. Record form, temper and the required stock tolerance. [Mueller product reference](https://muellerbrass.com/products/c36000/), [Wieland Chase selection guide](https://wieland-chase.com/brass-selection-guide/)

Wieland identifies **Z23 / CuZn36Pb3 / CW603N** with C36000. Confirm the actual product specification and supplied state before substitution. [Wieland Z23 datasheet](https://www.wieland.com/content/download/9839/file/Z23_EX_EN.pdf)

## Machinability is a relative rating

Mueller rates C36000 machinability **100%**, cold-working capacity moderate and hot-working capacity poor. Wieland Z23 instead reports machinability **90% against CuZn39Pb3 = 100%**, and rates hot working good. The different references and product guidance should remain visible; do not combine them into a universal machining score or forming procedure. [Mueller workability table](https://muellerbrass.com/products/c36000/), [Wieland Z23 fabrication properties](https://www.wieland.com/content/download/9839/file/Z23_EX_EN.pdf)

A rating of 100% does not mean 100% material yield, maximum possible spindle speed, or a guaranteed tool life. It helps compare materials within the stated rating system. For a production part, qualify the actual stock, tool material/geometry, coolant, machine rigidity, cut depth and chip evacuation. Record cycle time, burr condition, surface finish, dimensional capability and tool wear on representative runs.

Do not replace a functional alloy requirement with whichever brass machines fastest. A change made for machining productivity can also change strength, joining behavior, corrosion performance or lead obligations. Likewise, a supplier's favorable machining statement does not establish that a thin wall, cross-hole intersection or sealing surface can be made to an arbitrary tolerance without trials.

## Size, temper and acceptance properties

Mueller's product page labels its **56 ksi tensile, 45 ksi yield, 25% elongation and Rockwell B 72** values **typical** without attaching a complete size/temper condition to that table. Those numbers should not become drawing minima for all bar sizes. [Mueller typical mechanical properties](https://muellerbrass.com/products/c36000/)

For comparison, Wieland Chase's C36000 sell sheet labels its table **minimum mechanical properties** and varies it by diameter:

| Diameter in the supplier table | Tensile | Yield | Elongation |
| --- | --- | --- | --- |
| 0.500–1.000 in | 55 ksi | 25 ksi | 10% |
| >1.000–2.000 in | 50 ksi | 20 ksi | 15% |

Use these as the named supplier's entries; confirm ordered temper, size boundaries and contractual test requirements. The same sheet gives round-bar diameter tolerances of **±0.0020 in** for **>0.500–1.000 in**, and **±0.0025 in** for **>1.000–2.000 in**. Stock tolerance is not finished machining tolerance. [Wieland Chase C36000 sell sheet](https://wieland-chase.com/wp-content/uploads/2024/01/WC-Alloy-Sell-Sheet-C36000.pdf)

For explicitly temper-based data, Wieland's Z23 round/polygonal-rod table gives **R400 tensile ≥400 MPa** for round diameters **2–25 mm**, while **R480 tensile ≥480 MPa** covers **2–14 mm** round diameters. Neither row qualifies other forms or sizes. [Z23 EN 12164 table](https://www.wieland.com/content/download/9839/file/Z23_EX_EN.pdf)

## Corrosion and exposure limits

Wieland warns about **stress-corrosion cracking under mechanical stress in an ammoniacal atmosphere**, and **dezincification in warm, acidic waters**. These are separate mechanisms and require exposure-specific assessment. A general “good corrosion resistance” claim is not a qualification for seawater, chemical cleaning or a loaded fitting. [Wieland Z23 corrosion guidance](https://www.wieland.com/content/download/9839/file/Z23_EX_EN.pdf)

AMPP describes dezincification as zinc removal leaving a weak, porous, copper-rich structure; attack may be localized or spread across a surface. That explains why retained external shape does not establish retained wall strength. Specify water chemistry, temperature, stagnation/flow, external environment and applied/residual stress, then require appropriate material and component evidence. Do not assign C36000 a dezincification-resistant designation merely from its UNS number. [AMPP dezincification reference](https://www.ampp.org/technical-research/what-is-corrosion/forms-of-corrosion/dezincification)

Z23's room-temperature reference values include electrical conductivity **13 MS/m / 22% IACS** and thermal conductivity **100 W/(m·K)**. [Z23 physical properties](https://www.wieland.com/content/download/9839/file/Z23_EX_EN.pdf)

## Lead, processing and suitability claims

A market/application listing is not approval for drinking-water, food-contact, medical or electrical-product use. Obtain the current, application-specific compliance statement and finished-component certification where required. Do not infer compliance from the presence of a plumbing application in a catalog.

One source inconsistency deserves explicit caution: the Chase C36000 sell sheet lists **2.5–3.0% lead** while also printing a **0.25% weighted-average wetted-surface lead-compliance** footnote. This page does not treat that footnote as evidence of suitability. Obtain clarification tied to the exact alloy and component rather than copying it into a material specification. [Chase source sheet](https://wieland-chase.com/wp-content/uploads/2024/01/WC-Alloy-Sell-Sheet-C36000.pdf)

The currently linked **Wieland Z23 US SDS, version 11, reviewed/printed June 14, 2022**, identifies C36000 and distinguishes solid metal from melting or operations generating dust, smoke or fume. It includes reproductive-hazard and other health warnings, instructions to avoid inhalation, handwashing and protective-equipment guidance. Obtain the current regional SDS for the actual supplier's stock before processing. An intact bar's handling conditions do not describe grinding debris or joining fume. [Wieland Z23 SDS](https://www.wieland.com/en/content/download/11086/file/Wieland-Z23-USA_EN.pdf?inLanguage=eng-GB)

Define process controls, cleaning and chip/scrap collection with the fabricator. Keep alloy identity through machining, plating and recycling, and assess airborne exposure for the actual operation. The SDS directs users to contact the manufacturer about recycling and excludes disposal with household garbage. [Z23 SDS, sections 8 and 13](https://www.wieland.com/en/content/download/11086/file/Wieland-Z23-USA_EN.pdf?inLanguage=eng-GB)

## Source versions and release

Sources were reviewed November 1, 2026. The Z23 technical PDF prints **08.19**; the SDS has the explicit 2022 dates above. The Chase sell sheet and Mueller product page have no visible technical revision date; the PDF's upload path is not a revision statement. Supplier data support selection, while the purchase specification and agreed inspection define acceptance.

Release against ordered chemistry/form/temper, dimensions, surface and functional requirements. Retain lot identity and distinguish typical data, contractual minima and actual test results.

[Grades, conditions and material selection](../grades-tempers-and-conditions.md)