Reference Library

Engineering Reference

Materials, ISO & unified thread tables, fits & tolerances, surface finish, hardness conversion, drill & tap charts, fasteners, bearings, steel profiles and more — all searchable.

201

Materials

Thread sizes

Hardness pts

370

Steel profiles

Material	Category	E GPa	Sy MPa	Su MPa	HB	ρ kg/m³	α ×10⁻⁶/°C	λ W/(m·K)
S235JR S235	Steel	210	235	370	120	7850	12	52.0
S275JR S275	Steel	210	275	430	140	7850	12	52.0
S355JR S355	Steel	210	355	510	165	7850	12	50.0
S420N S420	Steel	210	420	540	175	7850	12	50.0
S460N S460	Steel	210	460	570	185	7850	12	49.0
C45 C45	Steel	210	490	700	215	7850	11	48.0
C60 C60	Steel	210	580	850	255	7850	11	46.0
42CrMo4 4140	Steel	210	650	900	275	7850	12	42.0
34CrNiMo6 4340	Steel	210	800	1000	300	7850	12	38.0
16MnCr5 5115	Steel	210	635	880	285	7850	12	42.0
20MnCr5 5120	Steel	210	700	900	295	7850	12	42.0
100Cr6 52100	Steel	210	370	640	195	7850	12	46.0
X5CrNi18-10 (304) 304	Stainless Steel	200	210	520	130	7900	17	15.0
X2CrNiMo17-12-2 (316L) 316L	Stainless Steel	200	200	500	125	7980	17	15.0
X20Cr13 420	Stainless Steel	215	600	800	240	7700	11	25.0
X46Cr13 420B	Stainless Steel	215	650	900	270	7700	11	25.0
1050A 1050A	Aluminium	69	30	65	25	2705	23	222.0
2024-T3 2024	Aluminium	73	345	485	120	2780	23	121.0
6061-T6 6061	Aluminium	69	276	310	95	2700	23	167.0
6082-T6 6082	Aluminium	70	260	310	100	2710	23	170.0
7075-T6 7075	Aluminium	72	503	572	150	2810	23	130.0
AlSi9Cu3 226D	Aluminium	72	140	260	80	2790	21	96.0
CuZn37 (Brass) CW508L	Copper Alloy	100	120	360	90	8440	20	120.0
CuSn8 (Bronze) CW453K	Copper Alloy	105	170	420	130	8800	18	50.0
CuNi30 CW352H	Copper Alloy	150	170	420	120	8940	16	29.0
CuBe2 CW101C	Copper Alloy	128	1000	1200	360	8250	17	100.0
EN-GJL-200 GJL-200	Cast Iron	105	98	200	170	7150	11	48.0
EN-GJL-250 GJL-250	Cast Iron	115	165	250	210	7200	11	46.0
EN-GJS-400-15 GJS-400	Cast Iron	170	250	400	130	7100	12	36.0
EN-GJS-500-7 GJS-500	Cast Iron	170	320	500	185	7100	12	36.0
Ti-6Al-4V (Grade 5) Ti64	Titanium Alloy	114	880	950	330	4430	8.6	7.0
Ti Grade 2 Ti Gr2	Titanium Alloy	103	275	345	200	4510	8.6	16.0
PA66 (Nylon 66) PA66	Plastics	3	60	80	20	1140	80	0.2
PA66-GF30 PA66-GF30	Plastics	9	120	165	55	1380	30	0.3
POM (Delrin) POM	Plastics	3	67	68	22	1410	110	0.3
PEEK PEEK	Plastics	5	100	110	35	1320	50	0.3
PP (Polypropylene) PP	Plastics	2	30	35	10	910	120	0.2
ABS ABS	Plastics	2	40	45	15	1050	90	0.2
PC (Polycarbonate) PC	Plastics	2	62	65	20	1200	65	0.2
UHMWPE UHMWPE	Plastics	1	20	40	5	930	130	0.4
X153CrMoV12 (D2/1.2379) D2	Tool Steel	210	1700	2100	600	7700	11	20.0
X38CrMoV5-1 (H11/1.2343) H11	Tool Steel	210	1400	1700	480	7800	11	28.0
X40CrMoV5-1 (H13/1.2344) H13	Tool Steel	210	1450	1750	500	7800	11	25.0
S6-5-2 (M2/1.3343 HSS) M2	Tool Steel	220	2200	2700	840	8160	11	22.0
S6-5-2-5 (M35 Co-HSS) M35	Tool Steel	220	2400	2900	880	8200	11	20.0
90MnCrV8 (O1/1.2510) O1	Tool Steel	210	1500	1900	560	7830	12	35.0
105WCr6 (O7/1.2519) O7	Tool Steel	210	1600	2000	580	7870	12	35.0
40CrMnNiMo8-6-4 (P20/1.2311) P20	Tool Steel	205	900	1050	300	7830	12	36.0
EN-GJL-300 (GG30) GJL-300	Cast Iron	118	0	300	240	7250	11	48.0
EN-GJS-600-3 (GGG60) GJS-600	Cast Iron	172	370	600	220	7200	12	36.0
EN-GJS-700-2 (GGG70) GJS-700	Cast Iron	176	420	700	265	7250	12	35.0
EN-GJMW-360-12 (GTW35) GJMW-360	Cast Iron	175	190	360	130	7270	12	50.0
EN-GJMB-300-6 (GTS30) GJMB-300	Cast Iron	175	180	300	130	7200	12	45.0
Cu-ETP (C11000) C11000	Copper Alloy	120	70	220	45	8900	17	388.0
CuZn37 Brass (C27200) C27200	Copper Alloy	100	200	400	100	8440	21	115.0
CuZn39Pb3 Free-cutting (C38500) C38500	Copper Alloy	100	240	480	150	8500	21	113.0
CuZn40 (C28000) C28000	Copper Alloy	100	150	370	90	8400	21	120.0
CuSn8 Phosphor Bronze (C52100) C52100	Copper Alloy	110	380	600	180	8900	18	62.0
CuSn12 Tin Bronze (C90700) C90700	Copper Alloy	115	190	310	100	8800	18	50.0
CuAl10Ni5Fe4 Aluminium Bronze CuAl10Ni5	Copper Alloy	120	400	700	200	7600	16	59.0
CuBe2 Beryllium Bronze (C17200) C17200	Copper Alloy	130	1000	1250	360	8360	17	105.0
CuNi10Fe1Mn Cupronickel 10% CuNi10	Copper Alloy	150	180	380	110	8900	17	45.0
CuNi30Fe2Mn2 Cupronickel 30% CuNi30	Copper Alloy	160	220	480	140	8940	16	29.0
Ti Grade 1 (CP Ti) Ti Gr1	Titanium Alloy	102	170	240	100	4510	8.9	16.0
Ti Grade 2 (CP Ti) Ti Gr2	Titanium Alloy	103	275	345	120	4507	8.9	16.0
Ti-6Al-4V Grade 5 Ti-6-4	Titanium Alloy	114	880	950	310	4430	8.6	6.7
Ti-6Al-4V ELI Grade 23 Ti-6-4 ELI	Titanium Alloy	114	795	860	295	4430	8.6	6.7
Ti-3Al-2.5V Grade 9 Ti-3-2.5	Titanium Alloy	107	520	620	210	4480	8.3	8.0
Ti-10V-2Fe-3Al Ti-10-2-3	Titanium Alloy	107	1100	1170	360	4650	8.6	5.8
Inconel 625 (NiCr22Mo9Nb) IN625	Nickel Alloy	207	485	895	200	8440	13	10.0
Inconel 718 (NiCr19Fe19Nb5Mo3) IN718	Nickel Alloy	200	1100	1380	370	8190	13	11.4
Hastelloy C-276 (NiMo16Cr15W) C-276	Nickel Alloy	205	400	790	220	8890	11.2	10.2
Nimonic 90 (NiCr20Co18Ti) Nimonic 90	Nickel Alloy	220	825	1200	350	8180	12.7	12.0
Monel 400 (NiCu30) Monel 400	Nickel Alloy	180	240	550	160	8830	13.9	21.8
AZ31B Mg Alloy AZ31B	Magnesium Alloy	45	200	260	55	1770	26	77.0
AZ91D Mg Die Cast AZ91D	Magnesium Alloy	45	150	230	63	1810	26	72.0
AM60B Mg Alloy AM60B	Magnesium Alloy	45	130	220	60	1800	26	61.0
3003-H14 3003	Aluminium	69	145	170	40	2730	23	193.0
5052-H32 5052	Aluminium	70	195	230	60	2680	23	138.0
5083-H111 5083	Aluminium	70	145	290	75	2660	23	121.0
7050-T7452 7050	Aluminium	72	455	510	145	2830	23	157.0
7068-T6511 7068	Aluminium	72	620	665	190	2850	23	130.0
51CrV4 (1.8159) 51CrV4	Steel	206	1200	1350	390	7840	12	42.0
54SiCr6 (1.7102) 54SiCr6	Steel	206	1300	1450	420	7840	12	36.0
65Mn Spring Steel 65Mn	Steel	200	450	680	200	7820	12	40.0
17CrNiMo6 (1.6587) 17CrNiMo6	Steel	210	780	1000	300	7850	12	40.0
18CrNiMo7-6 (1.6587 DIN) 18CrNiMo7-6	Steel	210	800	1050	310	7850	12	40.0
18NiCrMo14-6 (1.6773) 18NiCrMo14-6	Steel	210	850	1100	330	7850	12	38.0
100CrMnSi6-4 (1.3520) 100CrMnSi6-4	Steel	210	400	660	200	7810	12	45.0
X65Cr13 Stainless Bearing X65Cr13	Steel	210	550	750	215	7700	11	24.0
PTFE (Teflon) PTFE	Plastics	1	14	25	5	2200	112	0.3
PPS (Ryton) PPS	Plastics	3	80	90	30	1350	50	0.3
HDPE HDPE	Plastics	1	25	30	8	960	130	0.5
PVDF (Kynar) PVDF	Plastics	2	35	55	18	1780	130	0.2
Natural Rubber (NR) NR	Elastomer	0	10	25	40	920	200	0.1
NBR (Buna-N) NBR	Elastomer	0	12	28	50	1000	170	0.3
EPDM EPDM	Elastomer	0	10	20	40	870	200	0.3
Silicone (VMQ) VMQ	Elastomer	0	8	12	30	1200	250	0.3
FKM (Viton) FKM	Elastomer	0	14	22	70	1850	160	0.3
S690QL S690	Steel	210	690	770	250	7850	12	48.0
S960QL S960	Steel	210	960	980	300	7850	12	48.0
25CrMo4 (1.7218) 4130	Steel	210	540	730	215	7850	12	42.0
50CrMo4 (1.7228) 50CrMo4	Steel	210	900	1100	330	7850	12	42.0
36CrNiMo4 (1.6511) 9840	Steel	210	750	950	285	7850	12	40.0
30CrNiMo8 (1.6580) 30CrNiMo8	Steel	210	900	1100	330	7850	12	39.0
C10 (1.0301) C10	Steel	210	300	490	155	7850	12	50.0
C15 (1.0401) C15	Steel	210	340	540	165	7850	12	50.0
C22 (1.0402) C22	Steel	210	380	600	180	7850	12	50.0
C35 (1.0501) C35	Steel	210	430	650	195	7850	12	49.0
C55 (1.0535) C55	Steel	210	540	800	240	7850	11	47.0
C75 (1.0614) C75	Steel	210	600	900	265	7850	11	45.0
38Cr2 (1.7003) 38Cr2	Steel	210	600	800	240	7850	12	44.0
41Cr4 (1.7035) 5140	Steel	210	660	900	270	7850	12	42.0
X2CrNi18-9 (304L) 304L	Stainless Steel	200	175	480	120	7900	17	15.0
X5CrNiMo17-12-2 (316) 316	Stainless Steel	200	220	530	135	7980	17	15.0
X6CrNiTi18-10 (321) 321	Stainless Steel	200	205	515	130	7900	17	16.0
X6CrNiNb18-10 (347) 347	Stainless Steel	200	205	515	130	7900	17	16.0
X2CrNiMoN22-5-3 (2205 Duplex) 2205	Stainless Steel	200	450	680	205	7800	13	19.0
X2CrNiMoN25-7-4 (Super Duplex 2507) 2507	Stainless Steel	200	550	750	235	7800	13	18.0
X12Cr13 (410) 410	Stainless Steel	215	500	700	220	7700	11	25.0
X10CrAlSi7 (430) 430	Stainless Steel	220	280	480	145	7700	10	26.0
X2CrTi12 (444) 444	Stainless Steel	220	240	430	130	7800	10	26.0
1100-H14 1100	Aluminium	69	105	125	32	2710	23	222.0
2011-T3 2011	Aluminium	70	310	370	95	2820	23	151.0
2014-T6 2014	Aluminium	73	415	485	135	2800	23	154.0
2017-T4 2017	Aluminium	72	275	425	105	2790	23	134.0
4032-T6 4032	Aluminium	79	315	380	120	2680	19	154.0
5005-H34 5005	Aluminium	69	165	200	55	2700	23	200.0
5454-H32 5454	Aluminium	70	200	270	73	2690	23	134.0
6063-T6 6063	Aluminium	69	215	245	73	2700	23	201.0
6351-T6 6351	Aluminium	69	285	310	95	2700	23	176.0
7020-T6 7020	Aluminium	72	350	400	120	2780	23	140.0
7075-T73 7075-T73	Aluminium	72	435	505	140	2810	23	130.0
X210Cr12 (D3/1.2080) D3	Tool Steel	210	1800	2200	620	7700	11	18.0
X165CrMoV12 (D6/1.2436) D6	Tool Steel	210	1750	2150	610	7700	11	19.0
100V1 (W1/1.1545) W1	Tool Steel	210	1450	1850	550	7820	12	38.0
45WCrV7 (S1/1.2550) S1	Tool Steel	210	1350	1700	500	7870	12	32.0
56NiCrMoV7 (L6/1.2713) L6	Tool Steel	210	1100	1400	420	7820	12	36.0
EN-GJL-150 (GG15) GJL-150	Cast Iron	100	0	150	140	7100	11	52.0
EN-GJL-350 (GG35) GJL-350	Cast Iron	130	0	350	265	7300	11	46.0
EN-GJS-350-22 (GGG35) GJS-350	Cast Iron	165	220	350	120	7100	12	36.0
EN-GJS-800-2 (GGG80) GJS-800	Cast Iron	176	480	800	295	7250	12	35.0
EN-GJV-300 (CGI 300) GJV-300	Cast Iron	140	190	300	180	7200	11	40.0
ADI Grade 900 (Austempered DI) ADI-900	Cast Iron	168	600	900	280	7100	12	22.0
Inconel 600 (NiCr15Fe8) IN600	Nickel Alloy	214	310	655	180	8470	13.3	14.9
Inconel 625 Cladding (alloy 625) IN625 Clad	Nickel Alloy	207	415	830	185	8440	13	10.0
Nimonic 80A (NiCr20TiAl) Nimonic 80A	Nickel Alloy	221	740	1090	320	8190	12.7	11.7
Hastelloy X (NiCrFeMo) Hast X	Nickel Alloy	197	360	745	210	8220	13.7	9.1
Waspaloy (NiCr19Co13Mo4Ti3Al) Waspaloy	Nickel Alloy	211	795	1275	370	8190	12.7	11.0
Invar 36 (FeNi36) Invar 36	Nickel Alloy	141	275	490	140	8100	1.2	10.0
Kovar (FeNiCo) Kovar	Nickel Alloy	138	280	520	150	8100	5.5	17.0
AZ61A Mg Alloy AZ61A	Magnesium Alloy	45	205	310	60	1770	26	70.0
AZ80A-T5 Mg Alloy AZ80A	Magnesium Alloy	45	250	340	75	1800	26	67.0
ZK60A-T5 Mg Alloy ZK60A	Magnesium Alloy	45	285	365	82	1830	26	62.0
WE43 Mg Alloy (Mg-Y-RE) WE43	Magnesium Alloy	44	200	270	70	1840	26	51.0
Ti-5Al-2.5Sn Grade 6 Ti-5-2.5	Titanium Alloy	110	760	830	265	4480	9.4	8.0
Ti-15V-3Cr-3Sn-3Al Ti-15-3	Titanium Alloy	100	760	800	250	4760	8.6	8.5
Ti-3Al-8V-6Cr-4Mo-4Zr (Beta C) Beta C	Titanium Alloy	103	1170	1240	385	4820	8.6	7.0
PA6 (Nylon 6) PA6	Plastics	3	55	75	18	1130	85	0.2
PA6-GF30 PA6-GF30	Plastics	9	110	155	50	1360	35	0.3
PET (Polyethylene Terephthalate) PET	Plastics	3	55	70	20	1380	70	0.2
PBT (Polybutylene Terephthalate) PBT	Plastics	3	55	65	18	1310	70	0.2
Epoxy (RTM) Epoxy	Plastics	4	50	75	20	1200	55	0.2
Phenolic (Bakelite) Phenolic	Plastics	6	40	55	25	1300	40	0.2
PMMA (Acrylic/Perspex) PMMA	Plastics	3	55	70	20	1190	70	0.2
PSU (Polysulfone) PSU	Plastics	3	70	80	22	1240	55	0.3
PAI (Torlon) PAI	Plastics	5	145	185	50	1420	31	0.3
PI (Vespel) PI	Plastics	3	80	95	30	1430	50	0.3
SBR (Styrene Butadiene) SBR	Elastomer	0	10	20	50	950	180	0.2
CR (Neoprene) CR	Elastomer	0	12	24	55	1230	180	0.2
IIR (Butyl Rubber) IIR	Elastomer	0	8	18	40	920	200	0.1
AU/EU (Polyurethane) PU	Elastomer	0	20	50	70	1200	150	0.3
ACM (Polyacrylate) ACM	Elastomer	0	10	18	55	1100	170	0.2
X2CrNiMo19-14 (316LN) 316LN	Stainless Steel	200	270	580	150	7980	17	15.0
X1CrNiMoCuN20-18-7 (904L) 904L	Stainless Steel	190	220	540	140	7980	16	12.0
X2CrNiMoN17-13-5 (317LMN) 317LMN	Stainless Steel	200	245	550	145	7990	17	14.0
40NiCrMo6 (1.6565) 4340 mod	Steel	210	820	1020	305	7850	12	39.0
X5CrNiCuNb16-4 (17-4 PH) 17-4 PH	Stainless Steel	197	1170	1310	388	7780	10.8	16.0
X7CrNiAl17-7 (17-7 PH) 17-7 PH	Stainless Steel	204	1030	1170	340	7800	10.2	16.0
X3CrNiMo13-4 (1.4313) CA6NM	Stainless Steel	200	620	800	245	7700	11	23.0
Tungsten (W) W Pure	Nickel Alloy	411	1500	1720	350	19300	4.5	173.0
Molybdenum (Mo) Mo Pure	Nickel Alloy	330	500	700	160	10200	4.8	138.0
CuCr1Zr (Chromium-Zirconium Cu) CuCr1Zr	Copper Alloy	125	350	420	130	8900	17	320.0
CuNiSi (Corson Bronze) CuNi3Si	Copper Alloy	130	600	700	190	8700	17	200.0
CuMg0.5 (Cadmium-free trolley wire) CuMg0.5	Copper Alloy	122	350	410	120	8900	17	360.0
EN-AC-46100 (AlSi11Cu2) 46100	Aluminium	72	140	250	75	2770	21	100.0
EN-AC-42100 (AlSi7Mg0.3) 42100	Aluminium	72	210	280	90	2680	22	155.0
EN-AC-45300 (AlSi5Cu3) 45300	Aluminium	71	200	290	90	2760	21	130.0
Stellite 6 (CoCr28W4) Stellite 6	Nickel Alloy	210	700	1050	380	8380	13	14.0
MP35N (NiCoCrMo) MP35N	Nickel Alloy	228	930	1070	320	8430	12	15.0
LDPE (Low Density PE) LDPE	Plastics	0	8	12	5	920	200	0.3
PP-GF30 PP-GF30	Plastics	6	80	90	28	1130	50	0.3
LCP (Liquid Crystal Polymer) LCP	Plastics	10	80	165	45	1400	7	0.3
EN-AW-2219-T851 2219	Aluminium	73	393	476	130	2840	22	121.0
6005A-T6 6005A	Aluminium	69	240	270	80	2700	23	190.0
X12CrMnNiN17-7-5 (Nitronic 50) Nitronic 50	Stainless Steel	200	380	760	210	7880	16	14.0
Maraging 300 (18Ni300) Maraging 300	Steel	190	1900	1985	570	8000	10	25.0
Maraging 250 (18Ni250) Maraging 250	Steel	190	1700	1800	520	8000	10	25.0
AISI 52100 (100Cr6 US) 52100	Steel	210	380	640	197	7830	12	46.0
HSS PM T15 (1.3202) T15 PM	Tool Steel	220	2600	3200	900	8200	11	21.0
X45CrSi9-3 (Valve steel) X45CrSi9-3	Steel	215	650	950	285	7700	11	20.0

201 of 201 shown — click a header to sort, a row to expand

Engineering Reference Library — Materials, Threads, Fits & Steel Profiles (EN / ISO)

The MechanixCalc Engineering Reference Library puts the core reference tables every mechanical engineer needs into a single, instantly searchable tool. The materials database covers 100+ grades across structural steels (EN 10025), alloy steels, stainless, aluminium alloys, copper alloys, cast irons, titanium alloys and engineering plastics — each with Young's modulus E, shear modulus G, yield strength Sy, ultimate strength Su, estimated endurance limit Se, Brinell hardness HB, thermal expansion coefficient α and thermal conductivity λ. Thread tables cover ISO metric coarse and fine threads (ISO 261/965) and unified threads (UNC/UNF), with stress areas, minor diameters and pitch dimensions. ISO 286 fits and tolerances, hardness conversions (HB ↔ HRC ↔ HRB ↔ HV ↔ tensile), drill and tap charts, and steel profile section properties (IPE, HEA, HEB, IPN, UPN, W-shapes, S-shapes, CHS, SHS, RHS, equal and unequal angles) complete the dataset.

The library is built for practising engineers who need a verified reference number quickly — without hunting through multiple standards documents or manufacturer PDFs. All datasets are drawn from authoritative sources (EN 10025, ISO 261, ISO 286, ISO 273, EN ISO 898, ASTM A6, EN 10365) and are freely accessible with no sign-up required. Use it alongside any MechanixCalc calculator: look up a material's properties before entering them into the shaft or gear tool, check a thread's stress area before sizing a bolt, or verify a steel beam's second moment of area before running a beam analysis.

What this calculator does

100+ engineering materials with full mechanical and thermal properties (E, G, ν, ρ, Sy, Su, Se, HB, α, λ) — structural steels, alloy steels, stainless, aluminium, copper alloys, cast irons, titanium, plastics and more (EN 10025, ASTM, EN/ISO grades)
ISO metric coarse and fine thread tables (ISO 261/965) and unified thread tables (UNC/UNF) — pitch, major/minor/pitch diameters, stress area and root diameter, instantly searchable by nominal size
ISO 286-1 fits and tolerances with hole-basis and shaft-basis codes — fundamental deviations, tolerance grades (IT5–IT11) and typical applications for all standard fit combinations
Hardness conversion table (HB, HRC, HRB, HV and equivalent tensile strength) based on ISO 18265 / ASTM E140 cross-reference data, covering the full practical hardness range
Drill and tap charts per ISO 273 for ISO metric coarse threads — recommended tap drill diameter and clearance drill size for each standard thread pitch
Steel profile section properties for 15 profile families: IPE, IPN, HEA, HEB, HEM, UPN, UB, UC, W-shapes, S-shapes, CHS, SHS, RHS, equal angles and unequal angles — area, Ix, Iy, Wx, Wy, ix, iy, mass per metre (EN 10365, ASTM A6)
Radar-chart mechanical-property comparison and stress-strain curve overlay for any two selected materials — strength, stiffness, density and thermal properties shown at a glance

Method & formulas

Material properties and endurance limit estimation

Mechanical properties (E, G, Sy, Su, HB) are tabulated from the authoritative material standards (EN 10025 for structural steels, manufacturer data for alloy and specialty grades). The estimated endurance limit Se for steels is derived from the empirical Shigley relation: Se ≈ 0.5 · Su for Su ≤ 1400 MPa, based on rotating-beam fatigue test data. Non-ferrous materials (aluminium, copper alloys, cast iron, stainless austenitic) do not exhibit a true endurance limit; Se is set to zero and a fatigue strength at a specified cycle count should be used instead. The thermal expansion coefficient α and thermal conductivity λ are nominal room-temperature values taken from standard references and are not corrected for elevated temperature.

Steel endurance limit estimate (Shigley)

Se ≈ 0.5 · Su [for Su ≤ 1400 MPa]

where Se = estimated uncorrected endurance limit (MPa); Su = ultimate tensile strength (MPa). This is an empirical approximation for steels; actual fatigue strength depends on surface finish, size, load type and stress-concentration factors.

ISO 286 fits and tolerances

ISO 286-1 defines fits through a system of fundamental deviations (letters A–ZC for holes, a–zc for shafts) combined with tolerance grades (IT1–IT18). The fundamental deviation positions the tolerance zone relative to the nominal size; the tolerance grade specifies the width of the zone. For a given nominal diameter d and tolerance grade IT n, the tolerance value T is computed from the standard tolerance unit i and the grade multiplier: T = k · i, where i = 0.45 · ∛d + 0.001 · d (d in mm, i in µm). The Reference Library stores the computed upper and lower deviations for all common fit codes and nominal diameter steps, following the tables in ISO 286-1:2010.

ISO standard tolerance unit

i = 0.45 · ∛d + 0.001 · d [µm, d in mm]

where i = standard tolerance unit (µm); d = geometric mean of the nominal diameter step (mm). The tolerance value for grade ITn is then T = k_n · i, where k_n is the grade multiplier from Table 2 of ISO 286-1.

Steel profile section properties

Section properties (cross-sectional area A, second moments of area Ix and Iy about the principal centroidal axes, elastic section moduli Wx and Wy, radii of gyration ix and iy, and linear mass) are tabulated directly from the published standards: EN 10365 for European IPE, HEA, HEB, HEM, IPN, UPN and angle sections; BS 4-1 for UB and UC; ASTM A6 for American W and S shapes. No approximation is used — the values are the same as those in the standard tables and manufacturer section books. The relevant formula for moment capacity is shown below as a reminder of how section modulus Wx enters a beam bending check.

Elastic bending section modulus

Wx = Ix / y_max

where Wx = elastic section modulus about the x-axis (cm³); Ix = second moment of area about the x-axis (cm⁴); y_max = distance from centroid to extreme fibre (mm, half the total depth for doubly-symmetric sections).

Worked example

Identify the tolerance on a 50 mm nominal diameter shaft specified as 50 h6, and find the upper and lower limit dimensions. This is a common step when specifying a bearing seat or shaft–hub interference fit.

Given

Nominal diameter50 mm
Shaft tolerance codeh6

Result

Upper shaft limit (es = 0)50.000 mm
Lower shaft limit (ei = −16 µm)49.984 mm
Tolerance band T (IT6)16 µm

For the h deviation, the fundamental deviation (upper deviation es) is zero by definition: es = 0 µm. The shaft may be at or below the nominal size — never above.
Find the standard tolerance unit i for the 50 mm diameter step (30–50 mm range, geometric mean d = √(30 × 50) ≈ 38.73 mm): i = 0.45 · ∛38.73 + 0.001 · 38.73 = 0.45 × 3.382 + 0.03873 ≈ 1.521 + 0.039 ≈ 1.560 µm.
IT6 multiplier from ISO 286-1 Table 2 is k₆ = 10. Tolerance T = k₆ · i = 10 × 1.560 ≈ 16 µm (ISO rounds to 16 µm for this step).
Lower deviation: ei = es − T = 0 − 16 = −16 µm.
Shaft limits: upper limit = 50.000 mm; lower limit = 50.000 − 0.016 = 49.984 mm.

Illustrative — the Reference Library reads limits directly from the ISO 286-1 tables for all standard codes and diameter steps. Always verify against the current edition of ISO 286-1 for safety-critical fits.

Frequently asked questions

Which standard does the Engineering Reference Library use?

Different datasets use the relevant authoritative source for each subject: EN 10025 for structural steel grades; ISO 261 and ISO 965 for metric thread dimensions; ISO 286-1 for fits and tolerances; ISO 273 for drill and tap sizes; EN ISO 898-1 for fastener grades; EN 10365 for European steel profile section properties; ASTM A6 for American W and S shapes; ISO 18265 / ASTM E140 for hardness conversions. The governing reference for each datum is noted in the library.

Is the Reference Library free?

Yes — the Reference Library is permanently free with no sign-up required. A free 30-minute preview session (no sign-up) also gives access to every calculator on the platform, and a free 14-day account trial (no credit card) unlocks all tools. Saved calculations and branded PDF reports are included in the free 14-day trial and in every paid plan.

How do I find material properties for a specific grade?

Use the search bar in the Materials tab — type any part of the grade name (e.g. '42CrMo4', 'S355', '6061', '304') and the library filters the table instantly. Select a material to expand the full property card, which shows E, G, Sy, Su, Se, HB, α, λ, typical applications, heat-treatment condition and the governing standard. You can also compare any two materials side-by-side with the radar chart overlay.

Can I look up the tolerance band for any ISO fit code?

Yes. Open the Fits & Tolerances tab, enter the nominal diameter and select the hole and shaft codes (e.g. H7/h6, H7/p6, G7/h6). The library returns the upper and lower deviations, the tolerance band, the nominal clearance or interference range and a plain-language description of the fit type and typical applications.

Which steel profile families are included?

The library covers 15 profile families: IPE and IPN (European I-beams), HEA, HEB and HEM (European wide-flange beams), UPN (European channels), UB and UC (British universal beams and columns), W-shapes and S-shapes (American wide-flange and standard beams per ASTM A6), CHS (circular hollow sections), SHS and RHS (square and rectangular hollow sections), plus equal-leg and unequal-leg angles. Section properties listed are: area A, Ix, Iy, Wx, Wy, ix, iy and mass per metre.

Related calculators

Run the Engineering Reference Library on your own numbers

Free 30-minute preview — no sign-up. A free 14-day account trial unlocks every tool and the branded PDF report, no credit card required.

Start free

Using MechanixCalc at work? See plans & pricing — one subscription unlocks all 50 calculators, PDF reports and saved projects.