# Rubber Durometer and Elastomer Compound Reference

> Source: https://netray.co/tools/rubber-durometer-and-elastomer-compound-reference
> Publisher: Netray (netray.co), AI and integration engineering for ERP and manufacturing systems.
> Section: Free Tools

## Short answer

A searchable lookup of common elastomers with ASTM D1418 abbreviations, typical Shore A hardness, specific gravity, service temperature and fluid compatibility notes.

## Category

engineering-plm

## Industry

Rubber & Elastomer Products

## Audience

- Design engineer
- Estimator
- Buyer

## Tool

**Kind:** worksheet

**Mode:** reference

**Columns:**

#### Elastomer

**Key:** material

**Type:** text

#### ASTM D1418 code

**Key:** code

**Type:** text

#### Typical Shore A range

**Key:** shore

**Type:** text

#### Typical specific gravity

**Key:** sg

**Type:** text

#### Approx. service range (C)

**Key:** temp

**Type:** text

#### Strong against

**Key:** good

**Type:** text

#### Weak against

**Key:** weak

**Type:** text

#### Relative cost

**Key:** cost

**Type:** text

**Rows:**

**Material:** Nitrile (Buna-N)

**Code:** NBR

**Shore:** 40 to 90

**Sg:** 1.0 to 1.5

**Temp:** -30 to 100

**Good:** Petroleum oils, fuels, hydraulic fluids, water

**Weak:** Ozone, weathering, polar solvents, brake fluid

**Cost:** Low

**Material:** Hydrogenated nitrile

**Code:** HNBR

**Shore:** 50 to 90

**Sg:** 1.1 to 1.4

**Temp:** -30 to 150

**Good:** Hot oil, sour gas, abrasion, ozone

**Weak:** Polar solvents, ketones

**Cost:** Medium to high

**Material:** Ethylene propylene diene

**Code:** EPDM

**Shore:** 30 to 90

**Sg:** 1.0 to 1.3

**Temp:** -50 to 150

**Good:** Water, steam, brake fluid (glycol), ozone, weathering

**Weak:** Petroleum oils and fuels

**Cost:** Low

**Material:** Fluoroelastomer (Viton type)

**Code:** FKM

**Shore:** 55 to 90

**Sg:** 1.8 to 2.0

**Temp:** -20 to 200

**Good:** Fuels, oils, many acids, heat

**Weak:** Ketones, hot water or steam, amines

**Cost:** High

**Material:** Perfluoroelastomer

**Code:** FFKM

**Shore:** 65 to 90

**Sg:** 2.0 to 2.2

**Temp:** -15 to 260

**Good:** Nearly all chemicals, very high heat

**Weak:** Cost, low-temperature flexibility

**Cost:** Very high

**Material:** Silicone (methyl vinyl)

**Code:** VMQ

**Shore:** 20 to 80

**Sg:** 1.1 to 1.3

**Temp:** -55 to 200

**Good:** Wide temperature range, ozone, food and medical grades

**Weak:** Tear and abrasion strength, hydrocarbon fuels

**Cost:** Medium

**Material:** Fluorosilicone

**Code:** FVMQ

**Shore:** 40 to 80

**Sg:** 1.3 to 1.5

**Temp:** -60 to 175

**Good:** Fuels and oils with low-temperature flexibility

**Weak:** Tear strength, cost

**Cost:** High

**Material:** Polychloroprene (Neoprene)

**Code:** CR

**Shore:** 30 to 90

**Sg:** 1.2 to 1.5

**Temp:** -40 to 100

**Good:** Weathering, flame resistance, moderate oils, refrigerants

**Weak:** Strong oxidizers, aromatic solvents

**Cost:** Low to medium

**Material:** Natural rubber

**Code:** NR

**Shore:** 30 to 90

**Sg:** 0.95 to 1.3

**Temp:** -50 to 80

**Good:** Resilience, tear and fatigue, abrasion

**Weak:** Oils, ozone, heat

**Cost:** Low

**Material:** Styrene butadiene

**Code:** SBR

**Shore:** 40 to 90

**Sg:** 1.0 to 1.3

**Temp:** -50 to 100

**Good:** Abrasion, water, general purpose

**Weak:** Oils, ozone

**Cost:** Low

**Material:** Butyl

**Code:** IIR

**Shore:** 40 to 80

**Sg:** 0.9 to 1.3

**Temp:** -45 to 120

**Good:** Low gas permeability, ozone, vibration damping

**Weak:** Petroleum oils

**Cost:** Low to medium

**Material:** Chlorosulfonated polyethylene

**Code:** CSM

**Shore:** 50 to 90

**Sg:** 1.1 to 1.5

**Temp:** -30 to 120

**Good:** Ozone, weathering, oxidizing chemicals

**Weak:** Aromatic and chlorinated solvents

**Cost:** Medium

**Material:** Polyacrylate

**Code:** ACM

**Shore:** 50 to 90

**Sg:** 1.1 to 1.4

**Temp:** -20 to 150

**Good:** Hot oil, transmission fluid, ozone

**Weak:** Water, steam, low-temperature flexibility

**Cost:** Medium

**Material:** Ethylene acrylic

**Code:** AEM

**Shore:** 40 to 90

**Sg:** 1.1 to 1.4

**Temp:** -30 to 160

**Good:** Hot oil, ozone, wide fluid mix

**Weak:** Fuels, strong acids

**Cost:** Medium

**Material:** Epichlorohydrin

**Code:** ECO

**Shore:** 40 to 90

**Sg:** 1.3 to 1.6

**Temp:** -40 to 130

**Good:** Fuels, ozone, low gas permeability

**Weak:** Steam, strong acids

**Cost:** Medium

**Material:** Polyurethane (cast or millable)

**Code:** AU / EU

**Shore:** 60A to 75D

**Sg:** 1.1 to 1.3

**Temp:** -40 to 80

**Good:** Abrasion, tear, load bearing, oils

**Weak:** Hot water, steam, acids

**Cost:** Medium

**Notes:** Values are typical industry ranges for general guidance, not specifications. Real compounds vary with fillers, cure system and grade, so always check the supplier data sheet and test against the actual fluid, temperature and duration. Shore A is measured with a durometer per ASTM D2240 or ISO 48-4: roughly 30 to 40 is soft like a rubber band to a pencil eraser, 60 to 70 is firm like a tire tread, and 90 is hard like a shoe heel. Shore D is used for harder plastics and urethanes.

## Content

**Intro:** Choosing a rubber compound starts with a short list of families, and the same questions come up on every inquiry: what fluid, what temperature, what hardness and what density. This reference puts the common elastomers side by side so you can narrow choices and fill in specific gravity for the weight calculators.

**Sections:**

#### How to use it

**Body:** Search by abbreviation or by the fluid or property you care about, for example oil, steam or ozone. Compare the strong and weak columns with the part's environment, then use the typical specific gravity to feed the weight and cost calculators. The cost column helps an early budget conversation. Once you pick a family, request a data sheet for a specific compound, since two NBR 70 materials can differ in density, fluid swell and compression set.

**Bullets:**

- Match the fluid first, then temperature, then hardness.
- Check low-temperature limits for outdoor and aerospace use.
- Treat the ranges as starting points, not specifications.

#### Understanding durometer

**Body:** Hardness is reported on a Shore scale measured with an indenter and a calibrated spring, standardized in ASTM D2240 and ISO 48-4. Shore A covers soft to medium-hard rubber from about 20 to 90, and Shore D covers harder materials. Readings are sensitive to specimen thickness (at least 6 mm is typical for a stable reading), temperature and dwell time, so a molded part may read a few points differently from a test slab. Tolerances of plus or minus 5 points are common on drawings.

#### Compound naming and callouts

**Body:** ASTM D1418 gives each rubber a short code such as NBR, EPDM or FKM. Specifications such as ASTM D2000 and SAE J200 use a line callout that combines type, class, hardness, tensile strength and suffix requirements for heat, fluid and compression set. Customers and drawings may instead cite a military, OEM or proprietary compound number. Always capture the full callout at quote time, because it controls which materials are allowed.

#### Common mistakes

**Body:** Common errors include specifying EPDM for an oil seal, using standard FKM in hot water or steam where a peroxide-cured grade is needed, and overlooking that silicone is weak in tear strength and in hydrocarbon fuels. Another is ordering by durometer alone: a 70 Shore A NBR and a 70 Shore A silicone behave completely differently in fluid, heat and wear. Match the compound to the environment, not only the hardness.

**Cta:** If your item master holds compound codes inconsistently, Netray can help normalize them and link them to specific gravity and cost for quoting. Ask for a review of your material data.

**Faq:**

#### What does Shore A durometer mean?

**Answer:** It is a hardness reading from an indenter pressed into rubber, defined in ASTM D2240 and ISO 48-4. Higher numbers mean harder material. Most rubber parts fall between 40 and 90 Shore A, with 70 being a very common general-purpose value.

#### Which rubber is best for oil resistance?

**Answer:** NBR is the economical standard for petroleum oils and fuels. HNBR, FKM and ACM handle hotter oil. EPDM and natural rubber swell badly in petroleum, so avoid them for oil contact.

#### Which elastomer has the widest temperature range?

**Answer:** Silicone offers a very wide range, roughly -55 to 200 C, and fluorosilicone adds fuel resistance. FFKM reaches the highest heat but has poor low-temperature flexibility and very high cost.

#### Is specific gravity the same for all compounds of one type?

**Answer:** No. Fillers, plasticizers and fluoropolymer content change density. NBR can range from about 1.0 to 1.5 depending on formulation. Use the figure from the data sheet for the exact compound when calculating weight and cost.

## Search terms

rubber durometer chart, shore a hardness rubber chart, elastomer comparison table, NBR vs EPDM vs FKM, rubber compound selection guide, ASTM D1418 rubber abbreviations, elastomer temperature range chart, rubber specific gravity table

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