# Solder Alloy Melting Point Reference Table: SAC305, Sn63Pb37 and More

> Source: https://netray.co/tools/solder-alloy-melting-point-reference-table
> Publisher: Netray (netray.co), AI and integration engineering for ERP and manufacturing systems.
> Section: Free Tools

## Short answer

Look up common solder alloy compositions with solidus and liquidus temperatures, eutectic status and RoHS notes.

## Category

electronics

## Industry

Electronics Manufacturing

## Audience

- Process engineer
- SMT engineer
- Quality engineer

## Tool

**Kind:** worksheet

**Mode:** reference

**Columns:**

#### Alloy

**Key:** alloy

**Type:** text

#### Common name

**Key:** common

**Type:** text

#### Solidus (deg C)

**Key:** solidus

**Type:** number

#### Liquidus (deg C)

**Key:** liquidus

**Type:** number

#### Type

**Key:** type

**Type:** select

**Options:**

- Eutectic
- Near-eutectic
- Non-eutectic

#### Lead-free

**Key:** rohs

**Type:** select

**Options:**

- Yes
- No

#### Typical use

**Key:** use

**Type:** text

**Rows:**

**Alloy:** Sn63Pb37

**Common:** Eutectic tin-lead

**Solidus:** 183

**Liquidus:** 183

**Type:** Eutectic

**Rohs:** No

**Use:** Legacy SMT and hand soldering where permitted

**Alloy:** Sn60Pb40

**Common:** 60/40 tin-lead

**Solidus:** 183

**Liquidus:** 190

**Type:** Non-eutectic

**Rohs:** No

**Use:** Hand soldering, wave

**Alloy:** Sn62Pb36Ag2

**Common:** Silver-bearing tin-lead

**Solidus:** 179

**Liquidus:** 179

**Type:** Eutectic

**Rohs:** No

**Use:** Silver-metallized parts, reduced leaching

**Alloy:** Sn96.5Ag3.0Cu0.5

**Common:** SAC305

**Solidus:** 217

**Liquidus:** 220

**Type:** Near-eutectic

**Rohs:** Yes

**Use:** Most common lead-free SMT paste

**Alloy:** Sn95.5Ag3.8Cu0.7

**Common:** SAC387

**Solidus:** 217

**Liquidus:** 220

**Type:** Near-eutectic

**Rohs:** Yes

**Use:** Lead-free SMT and wave in some regions

**Alloy:** Sn95.5Ag4.0Cu0.5

**Common:** SAC405

**Solidus:** 217

**Liquidus:** 220

**Type:** Near-eutectic

**Rohs:** Yes

**Use:** Lead-free SMT paste

**Alloy:** Sn99Ag0.3Cu0.7

**Common:** SAC0307

**Solidus:** 217

**Liquidus:** 228

**Type:** Non-eutectic

**Rohs:** Yes

**Use:** Low-silver lead-free paste and wave

**Alloy:** Sn99.3Cu0.7

**Common:** Tin-copper

**Solidus:** 227

**Liquidus:** 227

**Type:** Eutectic

**Rohs:** Yes

**Use:** Lead-free wave soldering

**Alloy:** Sn96.5Ag3.5

**Common:** Tin-silver

**Solidus:** 221

**Liquidus:** 221

**Type:** Eutectic

**Rohs:** Yes

**Use:** Lead-free assembly, step soldering

**Alloy:** Sn42Bi58

**Common:** Tin-bismuth

**Solidus:** 138

**Liquidus:** 138

**Type:** Eutectic

**Rohs:** Yes

**Use:** Low-temperature reflow for heat-sensitive parts

**Alloy:** Sn91Zn9

**Common:** Tin-zinc

**Solidus:** 199

**Liquidus:** 199

**Type:** Eutectic

**Rohs:** Yes

**Use:** Niche applications, needs controlled atmosphere

**Alloy:** Sn95Sb5

**Common:** Tin-antimony

**Solidus:** 235

**Liquidus:** 240

**Type:** Non-eutectic

**Rohs:** Yes

**Use:** Higher temperature joints, step soldering

**Alloy:** In52Sn48

**Common:** Indium-tin

**Solidus:** 118

**Liquidus:** 118

**Type:** Eutectic

**Rohs:** Yes

**Use:** Very low temperature, thermally sensitive parts

**Alloy:** Au80Sn20

**Common:** Gold-tin

**Solidus:** 280

**Liquidus:** 280

**Type:** Eutectic

**Rohs:** Yes

**Use:** Hermetic packages, optoelectronics die attach

**Alloy:** Pb92.5Sn5Ag2.5

**Common:** High-lead

**Solidus:** 287

**Liquidus:** 296

**Type:** Non-eutectic

**Rohs:** No

**Use:** High-temperature die attach (exempt uses only)

**Alloy:** Pb95Sn5

**Common:** 95/5 high-lead

**Solidus:** 308

**Liquidus:** 312

**Type:** Non-eutectic

**Rohs:** No

**Use:** High-temperature step soldering (exempt uses only)

**Notes:** Temperatures are nominal and vary slightly by source and measurement method. Confirm against your paste or wire datasheet. RoHS status refers to the alloy's lead content; exemptions and customer rules vary.

## Content

**Intro:** When you set a reflow profile, choose a repair alloy or review a customer spec, you need the melting range of the alloy in front of you. This reference lists common solder alloys with composition, solidus and liquidus temperatures.

**Sections:**

#### How to use the table

**Body:** Search by alloy name, common name such as SAC305, or use. Solidus is the temperature at which melting begins and liquidus is where the alloy is fully liquid. For a eutectic alloy the two are equal. Your reflow profile must take the joint comfortably above liquidus and hold for the time above liquidus (TAL) in the paste datasheet. Export the table to PDF or Excel for your process documentation.

**Bullets:**

- Pb-free SAC alloys reflow with peaks well above 235 deg C
- Sn42Bi58 enables peak temperatures near 170 deg C
- Mixing alloys on one board needs extra care at rework

#### Reading the numbers

**Body:** The gap between solidus and liquidus is the pasty range. Non-eutectic alloys such as SAC0307 solidify over a wider range, which can lead to disturbed joints if parts move during cooling. Near-eutectic SAC alloys have a narrow 3 degree range and behave almost like a eutectic. Peak reflow temperature is typically 15 to 30 degrees above liquidus for lead-free, limited by the component maximum from J-STD-020.

#### Common mistakes

**Body:** A frequent mistake is reflowing a Sn-Pb board with a lead-free profile or the reverse, which damages parts or gives unwetted joints. Backward compatibility between Pb-free parts and Sn-Pb solder is a particular issue for BGAs, where the ball may not collapse fully. Low-temperature bismuth alloys also contaminate Sn-Pb and SAC joints if mixed, creating weak low-melting phases. Verify alloy, flux type and datasheet profile before every new product release.

**Cta:** Netray can connect process documents such as alloy and profile specs to the item and routing records in your ERP so operators work from the controlled version.

**Faq:**

#### What is the melting point of SAC305?

**Answer:** SAC305 (Sn96.5Ag3.0Cu0.5) begins melting at about 217 deg C and is fully liquid at about 220 deg C. Reflow peak temperatures are normally set 15 to 30 degrees above that, within the component limits.

#### What is a eutectic solder?

**Answer:** A eutectic alloy melts and solidifies at one single temperature rather than over a range. Sn63Pb37 at 183 deg C and Sn42Bi58 at 138 deg C are well-known examples. This gives sharp solidification and fewer disturbed joints.

#### Can I mix lead-free and tin-lead solder?

**Answer:** It is possible but risky. Mixed alloys can form low-melting phases and unreliable joints, and Pb-free BGAs on Sn-Pb profiles may not collapse fully. Follow your customer's requirements and IPC guidance, and avoid mixing where reliability matters.

#### Why is solidus different from liquidus?

**Answer:** Alloys that are not at a eutectic composition melt over a temperature range. Solidus is where the first liquid forms and liquidus is where the last solid dissolves. Reflow must exceed the liquidus to form a proper joint.

## Search terms

solder alloy melting point, sac305 melting point, sn63pb37 melting point, lead free solder melting temperature chart, solder alloy composition table, sn42bi58 low temperature solder, solder solidus liquidus, solder alloy reference chart

---
Talk to an engineer: https://netray.co/contact?intent=erp_ai | Machine catalog: https://netray.co/agent/catalog.json