IS 3195:1992 60Si7 Steel: Specifications & Listings
IS 3195:1992 60Si7: Hot-rolled silicon-manganese spring steel 60Si7 to IS 3195:1992 (third revision) as amended (Amendments 1 and 2), supplied as flats and rounds for volute and helical springs for railway rolling stock; the springs are worked hot and heat-treated. Maximum hardness in the annealed condition is 245 HB; the untreated hardness is about 255 HB for guidance.
Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Chemical Composition (%)
C
Mn
P
S
Si
0.55-0.65
0.80-1.00
<=0.030
<=0.030
1.50-2.00
Mechanical Properties
Hardness, annealed
<=245 HB
Hardness, untreated (hot rolled)
about 255 HB (for guidance only)
More data from IS 3195:1992
From the standard
Other composition limitsfrom the table notes and clauses
Values
Maximum unless a range is given (ladle analysis, as replaced by Amendment No. 1)
Product analysis, permitted variation over the limit
C plus or minus 0.03, Mn plus or minus 0.04, Si plus or minus 0.03 (plus or minus 0.05 above 0.40), S plus or minus 0.005, P plus or minus 0.005 percent
Product analysis rule
The variation does not apply both over and under the limits in several determinations in one heat
Incidental elements
Elements not quoted are not added intentionally without the purchaser's agreement, other than to finish the heat; elements from scrap that affect hardenability, mechanical properties or applicability are guarded against
Limiting bar diameter for springs (guidance)
Recommended for bars up to 32 mm
Steel making
Any process except the Bessemer process, followed by secondary refining or vacuum melting
Reduction ratio, minimum
16 to 1 from the ingot or continuous cast billet to the product; other ratios by agreement
Inclusion rating (IS 4163:1982), maximum
2.0 for A, B, C and D, thick and thin series (2.5 in the 1992 text, changed by Amendment No. 1)
Ladle analysis by IS 228 or another established method; the IS 228 method is the referee method. The 1992 text recommended bars up to 35 mm for this grade; Amendment No. 1 (1995) gives 32 mm. Amendment No. 1 lowered the sulphur and phosphorus maxima for this grade to 0.030 (0.040 or 0.035 in the 1992 text).
Source: IS 3195:1992 with Amendments 1 and 2, Table 1 (as replaced by Amendment No. 1), clauses 5, 6 and 9
Hardness by condition2 conditions
Untreated (hot rolled), for guidance only
about 255 HB
Annealed, maximum
245 HB
Hardness is tested to IS 1500:1983 on 2 percent of the bars of the same section and cast; the average of three readings must meet the limit (clause 13.2). For hot-rolled material other hardness limits may be agreed at enquiry and order (clause 7.1.1).
Source: IS 3195:1992 with Amendments 1 and 2, Table 2, clauses 7.1, 7.1.1 and 13.2
Permissible decarburization depthplain carbon and silicon-manganese steels
Maximum average total depth (partial plus complete)
0.15 mm plus 1.0 percent of the bar diameter
Measured on
The five deepest uniformly decarburized zones
Centreless ground bars
No decarburization permitted
For plain carbon and silicon-manganese spring steels (clause 8.6.1). Examined at 100 times magnification as per IS 6396:1983; 2 percent of the bars of the same section, and of each annealed batch, are tested (clauses 8.5 and 13.4).
Source: IS 3195:1992 with Amendments 1 and 2, clauses 8.6.1 and 8.6.3
Delivery condition and straightness3 conditions
Delivery condition (by agreement)
As-rolled and straightened; annealed and straightened; precision ground and peeled
Out of straightness, maximum
1.5 mm per metre for hot-rolled bars; 1.0 mm per metre for peeled and centreless ground bars
Surface
May be coated with a thin layer of anti-rust oil when agreed
Flats and rounds for volute and helical springs; the bars are worked hot and heat-treated by the spring maker. Peeled and centreless ground bars are supplied straightened (clauses 11.4 and 14).
Source: IS 3195:1992 with Amendments 1 and 2, clauses 11.4 and 14